T r €-!P.2. PREFACE ) On May 21 , School of Military nois was organized 1917, tile ins true t ional staff of the Aeronautics of the University of inl- and preliminary plans drawn up for the technical instruction. The staff was divided into groups to teach the various subjects, and the work on the notes was begun in preparation for the first class which would begin its technical instruction on June 11. It was planned to prepare comprehensive outlines of the work in each subject for each week and at the same time to look forward to the preparation of a complete set of Rotes which would be furnished in time to give to the first graduating class. Necessarily the work has been very hastily done and only through laborious revision will the notes be put into shape satisfactory to us. All material that has been available either to the government or to the individual members of the instructional staff has been used in their preparation, and illustrations used wherever available and advisable. It has been necessary in some cases to copy material directly from notes, pamphlets and books that we have received, because of the lack of time necessary for original presentation. If any writer or publisher finds that any of his or their work has been used, it is hoped that it will be excused on the basis of the gravity of the sources of information are too present emergency. The numerous to mention and no enumeration will be attempted. H. W. MILLER, Capt . Ord. Dept. President Academic Board July 13, 1917 . , Junior Wing* You should have these notes 3k 1 7^1. For each week as listed. Types of Machine Guns. #2 set. Description of Gun Parts. 4 sheets copy. 3 sheets of cuts. #3 set. Nomenclature of L»w?.3 Gun. 7 sheets copy. 1 sheet of cuts. #4 set. To strip and assemble the gun. 5 sheets of copy. Jk 2. #5 set. Spores and their care. 1 sheet. :k 5. $6 set. Lubrib&t iori of the Lewit Machixie Gun. Cleaning of gun. 3 sheets. #7 . set . Ammunition and Aiming. Types of Machine Guns. Vicer and. Lewis. Machine guns are divided into two classes according to their methc <-f operation and also according to the method used in codling the bar- re is . The two methods of operation are the recoil and gas while the '.'o cling of the barrel is obtained by water and air. The operation in i he heavier types of guns is by recoil where the recoil of the gun due to the hall leaving the barrel causes the mechanism to be thrown back? ~ spring brings the operating parts back to their initial position, in the gas operated guns a part of the gas of the explosion of the pow=- or r is tapped off and acting as a piston cause the mechanism to be thrown back by a spring which brings the operating parts, to their init- ial position as in the recoil gun. The Machine guns j n use today are classed as follows: Recoil and Water cooled guns are:- Vickers and Hotchkiss. Gas operated and Air Cooled are:- Lewis and Colt- At this time a description of the Vickers and Lewis gun will he taken up as these two guns are the ones you will deal with especially the Lewis gun which we take very thoroughly during your 30 hours of class work. The Vickers Gun is operated by the recoil and is more complicated than uhe Lewis* Gun™' The weight of the Vickers is 28-| lbs. without water and 30 lbs. with „the water. The method of feeding the cartrid^ ges to the gun is by the means of a belt which contains 250 rounds, a man being able to lead this belt at the rate of 25 rounds per minute. The rate of fire of the gun is from 500 to 700 rounds per minute the rate of firing being regulated by the tension of the fire or operat- ing spring and by a gas deflector which fits on the muzzle of the bar- rel. Because of this belt feed you can r eadily see that the gun in airplane work must he fixed for if you aimed the gun in different dir- ections it would twist the belt and cause a jamb. The cooling of the Vickers gun is obtained by putting 6 quarts of water into the water jacket which incases the barrel. Where the bar- rel comes through the water jacket there is "a box which is packed with asbestos to keep the water from leaking out. One minute of firing will bring the water to a boiling temperature and this is a disad- vantage in service as the steam given off might give the location of the gun away to the enemy. The Lev/ is Gun , is operated by gas and is so constructed that with shell, a wrench and parts of the gun used tools it can he strip- ped very quickly. The weight of the Lewis gun is 25 lbs. but as used in airplane work the radiator casing is taken off and radiator is turn ed down so that it only weighs IS pounds. The magazine of the Lewis gun is self contained, holding 47 rounds. At present time in Europe they are making a magazine which holds 97 instead of 47 it being four rows high instead of 2. The rate of fire of the gun is from 600 to 300 rounds per minute and is regulated by the gas regulating cup which has four different size port holes, and by the main spring. Because of the self contained magazine the L e wis gun can be fired in any dir- ection which is of a great advantage in airplane flights. The cool- ing of the barrel of the L e wis gun is accomplished by the gas rushing out of the barrel mouth piece and causing the air to be sucked in at the receiving end of the radiator and along the aluminum radiator fins aluminum being used for the radiator because of its lightness and Its high conductivity of heat. The barrel mouth piece with the assis- tance of the aluminum radiator also perform another important function which is of taking up of the recoil of the gun so that the L e ws gun ho no recoil- The function which makes the Lewis gun superior to the Vickers for airplane work are that first, it has a self contained magazine whil allows firing in any direction, second, it is air cooled because of which it is necessarily a lighter gun, and thirt, that there is no rec- oil . Summary of the Vicers and Lewis machine guns: Vickers Gun . 1. Operation by recoil. 2. Weight 28 lbs. without water and 38 lbs. with water. 3* Rate of fire 500 to 700 regulated by muzzle attachment. 4. Has a recoil. 5. Water cooled. 6. Belt feed 250 rounds. Lewis (j-un 1 4.0 lo - l. s t of cool ?Lng o • Tho 0 ^ y* ing piece ( 7 U ,*.«„* ... ... P?r?«aontXy .-.sscrtblod to the regr lock- Twga..z_nc und . t uhe oo. UV m -«-« u.-uh fcu &?ar„ lugs h^Mrmia&a .positron . uc- the rfsi^ar,^. -] ugS-.oi tne~ . .»_ boltV-'- T-he top- one of /these guiding, lugs g by engaging with the - eec operating arm ( 34 ), actuates the feea mechani-m. arm Ox Feed Operating Arirn- The feed operating and pivots around the magazine post (u) on nop It is secured in place hy the feed operating anri curved finger-like extension of the arm has in deeply cut groove, which, in action, engages witr feed operating stud (31). The main surface cj. ar the feed-way slot through which, in feeding, the from the magazine into the chamber . The feed pawl (35), the feed pawl stud ^r ; ^ (36), the feed pawl spring stud (q), and the feed mounted upon the feed operating arm (34). ( 34 ) fits over the receiver (26). latch ( 66 ). The s under side a the top lug of the e arm is pierced by cartridges pass the feed pawl spring pawl stop are all Stop and Rebound Pawls.- The stop pawl (23) and the rebound pawl 129TT are fitted int “place over the studs inside the _ feed cover (13), where they work against the magazine pawls spring (2/ Mainspring.- The mainspring (55) fits inside the mainspring casing ( 53 ), which is enclosed in the gear (52); and both are enclosed in the gear casing (61). One end of the coiled mainspring ( 55 ) is located by the mainspring rivets (59), the other end by the mainspring collet" (57), which is secured by the collet pin (56). It will be noted that the gear (52) engages inside the^gear casing (61) with the ratchet gear stop (46), which is held in place by the gear stop pin (48) and is actuated by the gear stop spring (49 Trigger Mechanism.- The trigger (30), enclosed -in the ^guard ( 39 ) ~ — ~~~ 1 " and secured by the grigger pin (33), is in mesh with the sear (91) and the sear spring box (42), which latter encloses the sear spring (41). Charging Handle.- The charging handle _( 3 V_L® n S a §? es the onera tTng - rod through a slot cut in the rack (72). It works through a narrow longitudinal slot cut through the side of the receiver (26). The charging handle may he inserted and used from either the right or left-hand side, as preferred. Safety.- The safety (32) Is a narrow sliding strip of steel wh i ch - serves both as a safety catch and as a dust cover for the longitudinal slot through which the charging handle moves. The .safety Vs used to lock the mechanism in the "ready-to-f eed" position. operated by pushing upward on the thumb -ho Ld until the notch engages with the shank of the charging handle (38) and then pulling the trigger (30). When this is done the charging handle is securely held beneath the undercut part of the notch (f ) and the whole me- chanism of the gun is locked. To release the safety, the charging handle is first pulled slightly back until the sear engages. A downward push then upon the projection (d) disengages the safety, a-d th p gun Is free to fire whenever the trigger is pulled. 5. IV . BUTTSTO CK The' "Rifle " and- "Spade... Grip' 1 ’ are- al-t.ernative'"'f drras -of. butts- took- ' / Z- • ... "'Rifle' ButistocK^- These parts consist of the huttplate (l),two buttplate screws ( 2 ) , the butt (3), the butt tang screw (4) and the butt tang (5). Together they form a single assembled piece, which should never be stripped. Spade Grip Buttstock.- This piece consists of the hand grip (92), and the spade gr'ip’TSutt tang (96). GENERAL NOTE It will be noted that the receiver group is secured to the barrel group by the receiver lock pin (68). The line of connection then runs through the gear casing (61) to the front end of the guard (39); through the guard to the butt latch (7) seated in a recess in its rear end. When the buttstock is latched into place behind the receiver (26), the entire gun is securely assembled. THE MAGAZINE The magazine from which cartridges are fed into gun is an assembled unit built up as follows: To magazine pan (43), by means of spacer ring rivets (69), is fastened the cartridge spacer ring (51), carrying the interior separators (70). Inside the pan is placed the magazine center (58), while outside is magazine top plate (67), which houses the magazine latch (62) and magazine latch spring (60). The magazine center and top plate are fastened together by means of magazine top plate rivets (54). The wall of magazine pan is provided with corrugations which on inside of pan serve to space and retain bases of cartridges, and on outside to engage with feed pawl (35), stop pawl (28), and rebound pawl (29). The magazine center is hollowed out and provided with a keyway so that it fits over magazine post and center key on top of receiver. When not in use, the pan and center are automatically locked to- gether by the magazine latch, which engages in a series of notches cut through inside edge of the spacer ring. To load or unload maga- zine the latch must be held back so that the pan may be free to re- volve around magazine center. In loading, latch is held back by magazine filling handle, which permits of pan being turned by hand or machine as cartridges are few down into place. In action, after magazine has been dropped into place over post on top of receiver, the latch is held back by a projection on inside oi this post, so that the pan is free to turn when acted upon by feed pawl. The magazine center is located and prevented from turning by the center key (63). In removing magazine, the latch is held back by hand while the magazine is lifted clear of post. f PLATES DESCRIPTIVE OF LEWIS GUN PARTS Plate 1. Complete with Magazine and Rifle Buttstock Plate 2. Gun parts: Barrel group and Operating Rod Plate 3. Gun parts: Receiver group, Mainspring and Trigger Mechanism NOMENCLATURE 'LIST OF PARTS IN GUN wo. 40. Cartridge Guide Spring. 40a. Cartridge Guide Lever. No . 1. Buttplate. 2. Buttplate Screws (2<). Lewis Automatic ... , v \ODliL Machine Gun 1916 ... mm bawc* at® •Arrrv- «i*mt ^Lerr /XQAPTyABUE TO/XNV / v VODERN/ v \u - lXARY C/XR.TRIDOB RAVAGE -ARMS CO UTICANY iJDAOLATt® C»SJNO CUAQ LOCK*** MCA (*_) Tflortr PAOIATOA CAfllNA OAWtfi. rAOUTMPlLCl 'LIST OF PARTS IN GUN Reference Name of part Reference Name of Part No No . 76 . Barrel . 77. Gas Cylinder. 89 . Barrel Mouthpiece. 84. Gas Regulator Cup. 37/ Bolt . 81. Gas Regulator Key. 7. Butt Latch. 52. Gear . 121. Butt Latch Pjni 65. Gear Case Hinge Pin. 10. Butt Latch Spring. 61. Gear Casing. 1. Buttplate . , Buttplate Screws (&). 46 . Gear Stop. 2. 48. Gear Stop Pin, 3. Buttstock , 49. Gear Stop Spring. 5. Butt Tang. 39. Guard . 4 . Butt Tang Screw. 22. Guard Side Pieces (2). 4Ci. Cartridge Guide Com.R 27. Magazine Pawls Spring. plete . 55 Mainspring 40. Cartridge Guide Spring. 53. Mainspring Casing. 40a. Cartridge Guide Lever 57. Mainspring Collet. 40b . Cartridge Guide Pin. 59. Mainspring Rivets. (2) 63. Center Key. 79 . Piston . 38. Charging Handle. 75 . Rack Assembling Spr'g. 85. Clamp Ling. 72. Rack . 87. Clamp Ring Position- 78' Radiator . ing Screw 90. Radiator Casing Front. 82h Clamp Ring Screw. 74. Radiator Casing Rear. 56. Collet Pin. 71. Radiator Casing Rear 21* Ejector . Locking Piece. 44. Ejector Cover. 29. Rebound Pawl . 45. Extractors (2). 26 . I Receiver . 13. Feed Cover. 68 . Receiver Lock Pin. 34. Feed Operating Arm. 52. Safety (Right and Left, 66 . Feed Operating Arm 91. Sear . Latch, 120. Sear Pin. 31. Feed Arm Actuating 41 . Sear Spring. Stud . 42. Sear Spring Box. 35. Feed Pawl. 28. Stop Pawl. 36. Feed Pawl Spring. 50. Striker . 86. Front Sight . 47. Striker Fixing Pin. 82. Gas Chamber. 30. Trigger . 83. Gas Chamber Band. 33. Trigger Pin. I COMPLETE NUMERICAL LIST OF PARTS IN LEWIS MACHINE GUN AND ACCESSORIES In order of the reference the text and illustrations. Reference Name of Part No . 1. Buttplate. 2. Buttplate Screws (2>). numbers used throughout in the Reference Name of Part No . 40. Cartridge Guide Spring. 40a. Cartridge Guide Lever. "eference N ane of Fart M o. 3. ^utts'ct^ek 4. Butt Tang Screw. 5* Lutt Tang. 7 . L utt Lat c h 8. Back Sight Bed Spring. 0. Back Sight Bed Spring Scraw. 10* Butt Latch Spri nr 11. Back Sic'ht Bed. 13. Feed Cover. 14. Back Sight Leaf. 20. Back Sight Slide. 21. Ejector. 22. ^uard Side Pieces (2) 23. Lack Sight Axis Pin Was he r . 24. Back Sight Axis Pin. 26. Receiver. 27. I/agazine Pawls Spring* 28 . Sto p Pawl . 29. Rebound Pawl* 30. Trigger. 31. Feed Operating Stud. 32. Safety (Right and Left) 33. Trigger Pin. 34. Feed Operating Ar,.;. 35. Feed Pawl. 36. Feed Pawl Spring. 37. Bolt 38. Charging Handle. 39. Guard. 401/2. Cart rid; :e Guide Com- plete . 72 Rack 74 .Radiator Casing Rear 75 Rack Assembling Spring 76 Barrel 77 Gras Cylinder 78 Piston A Regulation Key Stud 81 Cas Regulator Key 82 Gas Charter 83 Gas Ch.a_.be r Land Gas Regulator Cup 85 Clamp Ring 86 Front Sight Clamp Ring Positioning Screw Clamp fling Screw Reference Kane of Part No . 40 b » Cartridge Guide Pin. 41. Sear Spring. 42. Sear Spring Box. 4j . magazine Pan. 44. Ejector Cover. 45. Extractors (2) 46. Ca*r Stop. 47. Strike 1 * Fixing Pino 43. Gear Stop Pin 49a Gear Stop Spring* 50 a Striker. 51. Cartridge Spacer Ring. 52. Gear. 53. mainspring Casing* 54. Magazine Top Plate Rivets (6) 55. mainspring. 56. Collet Pin. 57. mainspring Collet. 53. Magazine Center. 59. mainspring Rivets . (2) 60). Gear Casing. 60, a~azine Latch Borin." . 62. magazine Latch. 63. Center Key. 65. Gear Case Kirwe Pin. 66. Feed Operating Am Latch 6 7 IS agazine Top Plate 68 Receive^- Lock Pin 6 9 Spacer Ring Rivets (5) 70 Interior Separator Pin 71. Radiator Casing Rear, Lod 112. Lountinr Yoke Pillar Screw 113 j ounting Yoke Clamp Hinge Pin 114. 1 . ounting Yoke Clam 0 Pin 115 haunting Yoke Cla p Key 116 Back Sight Elevating Screw 117 Back Sight Elevating Screw Head 118 Back Si r -ht Elevating Screw Head Pin 119 Eack Sight Elevating Screw Head Spring 120 Sear Pin 121 Butt Latch Pin piece 88 Name of Part : Jfcratftpl e ere-'. ' Sot Radiator Casing - Front . 91 . * Sear Rear. 92. Hand Grip. 96. - Spade Grip Butt Tang. 97. Deflector. 98. Deflector Arm. 99 . Deflector Arm Joint Pin. 100. Deflector Clip. 101. Deflector Clip Joint Pin . 102. Deflector Bracket. 103. Deflector Clamp Screw. 104. Deflector Latch. 105. Deflector Latch Screw. 106. Deflector Clamp Screw washer . 107. Defjectpr Clamp Screw Stop Nut, 108. Shell Catcher Bag. 109. Mounting Yoke. 110. Mounting Yoke Clamp. 111 . Mounting Yoke Pillar. Reference . Name . of. Part No-.- : , ■ A." - 122 . - 'Mount ing Y'Oke - Pillar > Hinge Pin. 123. Mounting Yoke Spring. ] 24 . Mounting Standard. 125 . Light Field Mount Bottom Crossbrace. 126. L.F.M. Center Post. 12$. L.F .M. Feet ( 2 ) . 128. L.F.M. Front Legs (2). 129. L.F.M. Front Yoke. 130. L.F.M. Knuckle Joint. 131. L.F.M. Knuckle Joint Pin. 132. L.F.M. Rear Brace. 133. L.F.M. T Joint, Center . 134. L.F.M. T Joint, Side ( 2 ) . 135. L.F .M. Top Lug. 136. Barrel Mouthpiece 137. Magazine Filling Han- dle . 138. Shell Extractor. OFFICIAL NOMENCLATURE The following list of parts showing the Official Nomen- clature given by the C.I.S.A. as to certain parts, is inserted for convenience of reference. Fact- ory No • Official ( C .1 . S . A . 7 Nomenclature Hand- Savage Arms Co. look Nomenclature No . F2-911 Fl-40 F2-1 Arms feed (with latch). 34-| F2-34 Arms feed. Fl-35 Latch, feed arm. E1-35A Stud, axis, lat- ch, feed arm. r.5 S’ " • ■'sod F2-45 Pawl, feed arm. Fl-46 Spring, pawl feed arm. Band, barrel. Barrel . Arm, feed operating. 34 Feed operating arm only . 66 Feed operating arm latch . 158 Feed operating arm latch rivet. 35 Feed Pawl. 36 Feed pawl spring. 83 Band, gas chamber. 76 Barrel. > F2-130 Bed, tangent sight. 11 Blades, foresight (high). Blades, foresight (low). F2-2 Body with hinge pin. 26 F2-915 Bolt complete (with 37-g- twoextractors and feed arm actuating stud). F2-3 Bolt only. Fl-10 Stud, actuating feed arm. F2-50 Extractors . Fl-29 Butt. 3 Fl-27 Cap butt. 5 Fl-11 Casing, pinion. 61-g- Casing pinion. Fl-14 Spring, return Fl-13 Casing, return spring , Fl-15 Hub, return spring , Fl-12 Pinion. Fl-17 Pawl pinion. Fi-16 Screw tension return spring. Fl-18 Spring, pawl pinion . Fl-19 Pin, axis, pawl pinion . 6- Disc, casing pinion . F2-6 Casing, radiator, front . 9©. F2-7 Casing, radiator rear . 74 F2-25 Catch, butt . 7 F2-39 Chamber, gas. 82 F2-31 Cover, body. 13 Fl-38 Cover, ejector. 44 Fl-43 Cylinder , gas . 77 Fl-37 Ejector . 21 F2-102A Foresight . 86 F2-24 Guard . 39 FI -51 Handle, cocking 38 F2-138. Head screw tangent si]ght - 117 PT-42 Key, gas regulator. 81 F2-135 ’ Leaf tangent sight. 14 F2-900 Magazine, complete. 43A F2-62 Magazine center. F2.-60A Magazine latch. Back sight bed. Blades, foresight (high). Blades, foresight (low). Receiver . Bolt complete (with two ex- tractors and feed arm act- uating stud), 37 Bolt. 31 Feed operating stud. 45 Extractors . Stock, Butt . Tang butt . Gear casing complete. 61 Gear casing. 55 Mainspring, 53 Mainspring casing, 57 Mainspring collet. 52 Gear , 46 Gear stop. 56 Collet pin. 49 Spring gear stop. 48 Pin gear stop. -- Disc, casing pinion. Casing, radiator, f rsnt . Casing, radiator, r<»ar . Latch, butt . Chamber, gas. ILover, feed. Cover, ejector. Cylinder, gas. Ejector . Sight, front (high and low). Guard. Handle, charging. Back sight elevating screw, head . Key, gas regulator. Back sight leit£. Magazine, complete. 58 Magazine center. 62 Magazine latch. Fac~ Official (C.I.S.A.) Hand- Savage- Arms Co*, \ Nomenclature book Nomenclature . No. pi-66 Magazine latch 60 Magazine latch spring . spring . F2-57A Magazine pan. 43 Magazine pan. Fl-59 Rivet, top plate 54 Magazine top plate magaz ine . rivet . F2-67A Pin, separating 70 Interior separator cartridge. * pin. F2-64 Cartridge spacer. 51 Cartridge spacer. F2-106 Cartridge head -- Cartridge head re- retaining pin. taining piece. Fl-65 Cartridge spacer 69 Cartridge spacer rivet . rivet . F2-58A Top plate maga- 67 Magazine top plate. z ine . FI -44 Mouthpiece barrel. 89 Mouthpiece barrel. F2-47 Pawl, stop magazine, left . 28 Pawl, stop. F2-48 Pawl, stop magaz ine , right . 29 Pawl, rebound. F2-131 Pin, axis, leaf, tangent 24 Back sight j axis, pin. s ight . F2-104 Pin, axis, sear. 120 Pin, sear. Fl-23 Pin, axis, trigger. 33 Pin, trigger. F2-139 Pin, fixing head screw 118 Back, sight, screw, head gent sight. pin . Fl-56 Pin, hinge, pinion, cas- 65 Pin, gear case hing. ing. Pin, butt latch. F2-106 Pin, keeper butt catch. 121 Fl-52 Pin, locking body. 68 Pin receiver lock. F2-132APin, split, keeper, axis Pin, split, keeper, axis pin, tangent sight. pin, tangent sight. Fl-30 Plate, butt. 1 Plate butt. F2-36 .Slate, safety catch, right. 32 Safety right. F2-36A Plate, safety catch, left • Safety left. - Plug clearing. 138 Shell extractor. F2-20A Plunger spring , trigger. 42 Sear spring box. F3-5 Radiator . 78 Radiator . F2-41 Regulator, gas. 84 Cup, gas regulator. F2-9 Ring, clamp. 85 Ring, clamp. F2-917 Rod, piston with rack and 79| Piston complete with rai pin. striker and striker fixing pin. F2-4E Piston. 79 Piston. F1-4A Rack actuating 72 Rack. bolt . Fl-32 Pin fixing rack 75 Spring, rack assem- piston rod. bling . F1-4B Striker. 50 Striker. Fl-40 Pin, fixing striker. 47 Pin, fixing striker. F2-134 Screw, bed and spring, tan- 9 Back sight bed spring. gent sight. Fl-28 Screw, butt cap. 4 Screw butt tang. Al-89 Screw, butt plate (2). 2 Screw butt plate (2). F2-8 Screw, clamp ring. 88 ; /* Screw , c lamp r ing , . • .♦ Back sight, elevating screv F2-137 Screw elevating, tang- 116 ent sight F2-103 Sear. 91 Sear. F2-55 Side piece pistol grip, 22 Piece Guard sight right. right. Piece Guard sight left. F2-55B Side piece pistol grip, left . F2-136 Slide tangent sight. 20 Back sight slide. F2-26 Spring, butt catch. 10 Spring r butt latch. F2-33 Spring, guide cartridge. 40|r Cartridge guide, complete. 40 Cartridge guide spring 4QA Cartridge guide lever . 40B Cartridge guide pin. F2-140 • Spring, head, screw, tan- 119 BA6k sight screw head gent sight. spring. Fl-49 Spring, pawls, stop. magazine . 27 Spring, magazine pawl. F2-133 Spring, tangent sight. 8 Back sight, bed spring. Fl-21 Spring, trigger. 41 Spring, sear. F2-9A Stud, positioning clamp 87 Screw, clamp ring p*»s- ring . it ioning . F2-22 Trigger , 30 Trigger . F2-132 Washer, pin, axis, tangent 23 Back sight, axis pin s ight . washer . ACCESSORIES AND TKEIR PARTS THE MAGAZINE (Plate 5) is an assembled unit composed of the following parts : 51. Cartridge spacer Ring. 70. Interior Separator Fin. 58, Magazine Center. 62. Magazine Latch. 60. Magazine Latch Spring. 43. Magazine Pan. 67. Magazine Top Plate. 54. Magazine Top Plate Rivets (6). 69. Spacer Ring Rivets (5). THE RIFLE BUTTSTOCK (Plate 6) is a single assembled piece composed of: 1. Buttplate. 2. Buttplate Screws (2). 3. Buttstock. 4. Butt Tang Screw. 5 • Butt Tang . THE SPADE GRIP BUTTSTOCK (Plate 6) is used when preferred tc the trifle- huttslock...., It ..is composed of the following parts- 92 . Hand Grip . 96. Spade Grip Butt Tang. THE SHELL DEFLECTOR (Plate 7) is an attachment for controlling the ejection of the empty cartridge cases. It is very readily and quickly attached and when in position can be instantly swung back out of the way so that the inside of the gun may be examined or any part of the mechanism reached. Plate 10 shows the deflector attached and ready to catch each cartridge ejected. One view shows the deflector swung back out of the way. The component parts of the shell deflector complete are as follows: 97. Deflector. 98. Deflector Arm. 99. Deflector Arm Jomht Pin. 102. Deflector Bracket. 103. Deflector Clamp Screw. 107. Deflector Clamp Screw Stop nut. 106. Deflector Clamp Screw Washer. 100. Deflector Clip. 101. Deflector Clip Joint Pin. 104. Deflector Latch. 105. Deflector Latch Screw. 108. Shell Catcher Bag. THE BACK SIGHT, a side view of which is shown in Plate 4, is normally left in position on top of the feed cover (13), where it is secured by the upper prolongation of the butt tang (4 or 96) and by the back sight bed spring screw (9). The back sight com- plete is an assembled unit composed of the following parts: 24. 23. 11 . 8 . 9. 116. 117. 118. 119. 14. 20 . Back Sight Axis Pin. B.S. Axis Pin Washer. B.S. Bed. B.S. Bed Spring. B.S, Bed Spring Screw B.S. Elevating Screw.' B.S. Elevating Screw B.S. Elevating Screw head Pin. B.S. Elevating Screw Head Spring. B.S. Leaf. B.S. Slide. THE MOUNTING YOKE (See Frontispiece and Plates 8, 9 and 10) is the device adopted to secure the gun on any desired form of mounting. The yoke complete is composed of following parts: 109. Mounting Yoke. 111. M.Y. Bronze Pillar. 123. M.Y. Spring. 110. M.Y. Clamp. 113. M.Y. Clamp Hinge Pin. .115. M.Y. Clamp Key. - - - . . .114 * M.Y .. Clamp Pin. ' ... 122. M.Y. Pillar Hinge Pin. 112. M.Y. Pillar Screw. AEROPLANE MOUNTING STANDARD.- This is a single gunmetal casting. (Plate 8: No. 124.) 124. Mounting Standard. LIGHT FOLDING FIELD MOUNT.- This is a three- and-a-half pound folding mount adapted for general use with infantry and cavalry in the field. The mount is surprisingly rigid and permit of very accurate shooting. Both front and rear mounting yokes, connected through the center post ahd rear brace, are pivoted about the axis of the center post, so that the gun is always free to traverse. The gun is free to turn within the yokes, so that the sights may always be kept vertical no matter what the pos- ition of the feet. When the mount is attached, it is often convenient to use the rear brace as a handle for carrying the gun. The assembled mount complete has the following component parts . 125. Light Field Mount Bottom Crossbrace. 126. L.F.M. Center Post. 127. L.F.M. Feet (2) . 128. L.F.M. Front Legs (2). 129. L.F.M. Front Yoke. 130. L.F.M. Knuckle Joint. 131. L.F.M. Knuckle Joint Pin. 132. L.F.M. Rear Brace. 133. L.F.M. T Joint, Center. 134. L.F.M. T Joint, Side (2). 135. L.F.M. Top Lug. also 1 Mounting Yoke Complete. Plate 7. Shell Deflector complete Plate 9. Light Folding Field Mount complete. Plate 8. Aeroplane Mounting complete. TO STRIP AND ASSEMBLE THE .GUN. - Although the gun may he taken apart starting with the mechan- ism in any position, it is best whenever practicable to see that the magazine is removed, the chamber empty and the charging handle at the extreme forward end of its stroke, before commencing to dismount. If this procedure is followed there will be no need to readjust the mainspring tension or to make any other adjustment when the gun is reassembled. STRIPPING To dismount the gun, insert the point of a bullet into the slot leading to the butt latch (Plate It No. 7) and push forward against the force of the butt latch spring. At the same time twist the buttstock (Plate 1: No. 3) up and to the left, then remove by withdrawing it to the rear. This removes the buttstock group, (Plate 6: Nos. 1,2, 3, 4 and 5) which should not be further dismounted . Next hold back the trigger (Plate 1: NO. 30), and pull back the guard (Plate 1: No. 39) until clear of the receiver (Plate 1: No. 26). This removes the guard, which contains the trigger mechanism and butt latch. Pull down on the gear casing (Plate 1: No. 61) until it drops clear of the rack (Plate 1: No. 72). Pull back the charging handle (Plate 1: No. 38i) until it reaches the end of its slot, then withdraw by pulling it out away from the receiver. Withdraw the operating rod complete and the bolt complete by pulling them both together to the rear until clear of the receiver. With the point of a bullet push back on the receiver lock pin (Plate 1: No. 68), then twist the receiver (Plate 1: No. 26) up and to the left and unscrew it from the barrel. The foregoing operations divide the gun into convenient groups of parts, the detailed stripping of which will not be described. DET AILED STRIPPING BUTTSTOCK GROUP It is best never to strip this group but if found necessary the screws securing the buttplate and butt tang- to the buttstock are readily removed. RECEIVER GROUP See that the feed operating arm (34) is pushed to the right, then pull back and remove the feed cover (13). FEED COVER.- From the feed cover the stop pawl (28), rebound pawl (29) and cartridge guide spring (40) are readily removed with the point of a bullet. In plate 4 these parts are seen in place inside the feed cover. BACK SIGHT. - The back sight (Plate 4: No. 11) may be stripped from the feed cover by removing the bed spring screw (9). 1 PEED OPERATING ARM. --Remove the- feed operating- arm complete (Plate 4; Nos , 34, 35, 36 and 66) by pushing forward on the feed operating "’'amr latch ■(■66-) "and thPn li f ting. cieer-of .tts'®agaz^ne, post (plate 3: (u)). The feed pawl (33) and feed pawl' spring-' 1 ^ / are removed from the feed operating arm by lifting them clear oi the studs (r) and (q)* The latph (66) should not be removed. i EJECTOR . *•- ( PI ate 4:Nos. 44‘ and 21). With the point Of ■ a bul- let lift and pull Out the ejector cover (44) and the ejector (21) * SAFETY. •** -The safeties (Plate 3: No. 32) may be pried out of the receiver with a bullet points / The gear case hinge pin (65) and the center key (63) are per- manently assembled and should not be removed. GEAR CASING.-- Push forward and remove the receiver lock pin (Plate 3: No. 68) and unhook gear casing (61) from the gear case hinge' pin ( 65 ) . The receiver group is now completely stripped. MAINSPRING GROUP To strip completely the parts (Plate 3: Nos. 61, 46, 56, 52, 57, 53, 55, 49, 48 and 59) found assembled in the gear casing (61), raise the gear stop (46) with the point of a bullet and allow the mainspring to unwind. 0 GEAR. --Then unscrew the collet pin (56) and shake out the gear ( 52 ) . MAINSPRING. --Pushing with a bullet through the gear against the mainspring collet (57) forces out the mainspring casing (53) from which the mainspring (55) with its locating rivets (59) and the mainspring collet (57) may also be removed by the use of a bullet. GEAR STOP. --The gear stop (46) and gear stop spring (49) should not be stripped but in case of necessity they may be removed by driving out the gear stop pjm (48), GUARD GROUP The assembled guard (Plate 3: Nos. 33, 120, 30, 91, 42, el, 121, 7 and 10) contains the trigger mechanism and the butt latch. To strip this group, punch out the trigger pin (33) and the sear pin ( 120 ) . TRIGGER. --Pull back on the trigger ( 3Q ) and lift it out. SEAR . --Remove the sear (91), sear spring box (42) and sear spring ( 41 ) . In ordinary pracice the guard group need never be stripped. BOLT AND ROD GROUP BUTT LATCH-- Punch out the butt latch pin (121) and remove the butt latch. (7) and butt latch spring (10)* The bolt and rod group comprises the holt complete and the operating red complete. These two assembled parts are withdrawn together from the receiver, and may then be separated by lifting the bolt clear of the operating post (m) on the rod. BOLT COMPLETE (Plate 4: Nos. 31, 45 & 37 ) PEED OPERATING STUD.-- Unscrevj and remove the feed operating stud (31) from the rear end of the bolt. EXTRACTORS.-- The extractors (45) are spring-tempered and are sprung into place. To remove, insert the point of a bullet under the extractor claw and push the head of the extractor out and away from the bolt. At the same time draw the whole extractor forward until it is clear of its seating. BOLT.-- The bolt (37) is now completely stripped. OPERATING ROD COMPLETE (Plate 2: Nos. 7S, 75, 72, 50 and 47.) This assembled piece is ordinarily never stripped. PISTON.-- The forward end of the rack assembling spring (75) may be pressed out of its notch in the piston (79) by the point of a bullet and piston can .then be readily turned out of the rack (72) STRIKER.-- The striker (50) may be withdrawn after punching out striker fixing pin (47). BARREL GROUP. (Plate 2: Nos. 81, 84, 88, 85, 86, 87, 90, 74, 71, 77, 89, 82, 76, 78, and 83.) GAS REGULATOR.-- Lift out the gas regulator key (81), then unscrew and remove the gas regulator cup (84). CLAMP RING.-- Using the gas regulator key as a tool, . unscrew the clamp ring screw (88) and remove the clamp ring (85), which carries the front sight (86) and clamp ring positioning screw (87). PAD I AT OR CASING.-- Pull forward the radiator casing front (90) and pull back the radiator casing rear (74), which is permanently assembled to the radiator casing rear locking piece (71) GAS CYLINDER. — Unscrew and remove the gas cylinder (77), using operating rod as a wrench. GAS CHAMBER-.' — Unscrew the-ghs- 'ch amber .(' 82 ) , using the •gae Teg- uits-loh'-^fey (81) -a./wre n oh, r -( PI,3,?£ * 2 ; uiig* A.) * - ' L" - - ' .'fBABREL iroTJEUPTECE. —Unscrew the 'ba.rrel mouthpiece- (89) r I e.nie'n- b-cr'lng that the thread on this piece' is lei t- handed . BARREL. --Drive out the "barrel (73) from the radiator (78). (This operation may conveniently be accomplished before removing the barrel mouthpiece by unscrewing the latter part way and thru allowing the barrel and radiator to drop from a height of two or three feet on to a solid piece of wood, striking on the front end of the barrel mouthpiece- The weight of the radiator dropping from this height will usually loosen the barrel sufficiently so that it can be simply withdrawn by hand from the radiator, after the mouthpiece has been removed.) GAS CHAMBER BAND. --Lift out the gas chamber hand (83) frorr._ its recess in the radiator*. The stripping of the barrel group is now complete. > ASSEMBLING By reversing the operations just given for stripping', the assembling of the gun is readily and quickly carried out.' The following points, however, should be noted: 1. Be sure that the gas chamber band (83) is correctly in- serted into its place in the radiator before the barrel (76) is pushed home and that the barrel is turned so that the gas port' (a) is at the bottom. 2. In replacing the bolt and operating rod the cam slot. in the bolt (37) is slipped over the striker (50); and the feed oper- ating stud (31) is screwed into the bolt as far as it will- go. 3. After inserting the bolt, rod and charging handle (38)., the charging handle is then carried forward to the extreme end of its stroke before the gear casing (61) is swung up into place and the rack engaged. 4. The mainspring is wound up by engaging the rack and gear, disengaging the guard and pulling back on the charging handle until the required tension is obtained. The gear is then disen- gaged, the charging handle moved completely forward the gear re- engaged and the guard pushed home. 5. To reduce the tension of the mainspring proceed as follows: Remove the buttstock. Disengage both guare£ and gear. Move the charging handle part way back. Reengage the gear and guard. Replace the buttstock. MAINSPRING TENSION The ideal condition exists when the strength of the mainsprin exactly balances the opposing force of the gas striking the piston head. When this condition is realized all parts of the gun are subjected to a minimum of shock and wear. The attainment of the exact point of balance is of no practical importance, for the gun will operate satisfactorily over a wide range on either side of _ this point. Besides, the exact point is subject to constant slight fluctuations, due to the variable frictions caused by oil or lacx of oil and the accumulation or removal of foreign matter within the mechanism. But a little attention paid by the gunner toward getting an approximate balance between gas and spring will be wel repaid in increased reliability of action and longer life of the gun' parts. For a given setting of the gas regulator the low limit for the working tension of the mainspring is the point at which mis- fires occur. The high limit is reached when the force of the gas is no longer sufficient to drive back the mechanism far enough to feed the succeeding cartridge. The gun will operate on any spring tension between these limits. At the approximate point of balance the bolt and rod barely touch the butt tang at the rear end of their stroke- Below this point the butt tang is being hammered with unnecessary force anc above it the action of the gun is faster than normal. As already pointed out, conditions inside the gun may vary the point of balance, hence it is sometimes advisable to increase the spring tension in order to overcome some added friction or prevent misfiring; or to slow down the rate of fire by slightly decreasing the tension. An average working tension for the mainspring is between twelve and fifteen pounds, as measured by holding back the trigger and pulling back on the charging handle with a small spring balance such as is supplied with the gun. S TARDARB IZED OPERA TI ON GEN ■Spade* Grip ' Item A. B. Tang Latch Operation 2- Body Cover Item’ A- Cartridge Guide Spring B. Stop Pawl, left #1 C- Stop Pawl, right #2 D- Magazine Pawl Spring Operation 3. Pistol Grip and Trigger Item A. Guard B. Sear C. Sear Axis Pin D. Trigger and Trigger Axis Pin E. Plunger F. Trigger Spring Operation 4, Feed Arm Item A. Feed' Arm Latch B. Feed Pawl and Spring C. Feed Pawl Spring Stud (tallest) D. Feed Pawl Stud (middle) E. Feed Pawl Stop Stud (smallest) Operation 5. Cocking Hangle Operation Bolt 6 . Item A. B. C. ID- Feed Arm Acting Extractors Camway Groove Resistance Lugs Stud Operation 7. Piston Rods Item A- B- C. D- E. Piston End Striker Pin Rack Sear Bent Striker Post Operation 8. Return Spring Group Item A. Pinion Pawl B- Tension Screw C. . Piston Casing D. Pinion E. Return Spring Case F. Return Spring - 2 - Oper-ation 10- Body Item A., Ejector Cover Ejector C- Safety Catch Plates Operation 11. ■ Pawl s . Stop Pawl left #1 Stop Pawl right #2 Peed pawl #3 The Magazine rotates clockwise- Pawl #1 prevents the magazine's turning anticlockwise. Pawl 2 prevents the magazine’s turning more than one space at a time. Pawl #3 is the feed pawl which pushes the magazine arour Operation 12- Barrel Group. Item A- Gas Regulator Key B. Gas Regulator Operation 13- Clamp Ring Item A. Radiator Casing Pront End B. Radiator Casing Rear End Operation 14. Gas Cylinder. Operation 15. Gas Chamber. Operation 16. Barrel Mouthpiece Left Hand Thread (Use Parrel mouthpiece spanner.) Operati on 17 . Knock Out Barrel Item A. Radiator Pins B. Gas Chamber Band A8 6th $ k. 3^3 fed# , P i Care «f Spares agd Inspection »f Gun. The c . re of spare ~>arts is a very important matter. Spares should be checked over atv-least once a week, and inspected by the Officer i/c of Guns. After checking, they should be wirapped in greased paper and returned to the receptacles provided. On no account should they be left lying loosely in the large boxes. The lids of gun boxes have been noticed during visits to the Expeditionary Force to be sometimes lying on the floor of the hangars, so allowing dust, etc. to enter the mechanism of a the guns and magazines. This could be obviated if in some manner the lids were hinged to the boxes. This could be done by means of ordinary "Butt" hinges, or by using leather or other suitable material. The lids should never be left off the boxes and this would obviate their loss. Having in view the fact that some little time is always needed to get a machine away from the ground, it would not seem necessary to keep guns mounted on machines, or standing in arm racks. They could be kept in their boxes until the time arrives for their need. Weekly Inspection of Guns. Guns, magazines and spares should be inspected by the Officer i/c guns at le:ast bnoe a week. Every gun should be stripped and parts laid out for inspection. This w ill necessitate the gas cylinder being removed, being the .only occasion upon which this will be necessary, whs* the gun has fired a total of about 500-600 rounds. this ex««P* LUBRICATION OP Mr THE LEWIS- MACHINE-GUN Owing to the extremely low temperature experienced at high altitudes during winter months too much oil must not bee applied to guns. Only the essential working nart should sLi: .v he oiled, these are: and striker posi: Bolt, camway groove Head of piston Worm of operating stud Slot in feed arm for operating stud Under surface csS feed arm Peed pawl (where it pivots on stud) Trigger mechanism St op 'pawl (at pivot) Rihs on under side of feed cover Teeth on main spring casing on piston Recoil lugs and their recesses. Lubrication of magazines The magazines should be taken separately and spun on a load- ing handle, to see if they work freely. A little oil should be ■vP the t ha t not applied to the junction of the outer and center port ions, ot magazines and catches. The lattei should be tested to sc its springs work freely as cases have been found of the catch returning°to its proper position end so failing to lock the magazine to magazine part. On no account should the cartridges be lubricated as this may cause abnormal pressure in the chamber upon firing. The oil to be used for the gams is of a special type known as oil for low temperatures for Lewis Machine-Guns. This oil has been adonted "after a long course of experiments, as the service rifle oil is liable to coagulate at the low temperature and intex- fere with the free working of the gun. * The soecial oil has sufficient viscosity to ensure adherence to th° working parts whilst at the same time it is of such a thin nature that it has not, been found to clog the working of the gun at a temperature of 11'" F * Sewing; machine, or instrument oil will take the place of ordinary rifle oil, but they must he applied to ^ just -orevioufj to its going up 'in a machine, otherwise the the gun oil will have run off; the working parts and the sufficient lubrication. gun will net havs Care and Cleaning of Gun Magazine, Spares, Etc . 1 st. If less than 800 rounds is fired, strip as far as the group , t ake out gas regulator. . ^ G Lon 1 if us e b o i 1 in sg y,m ter. \ I\;7 nrp t.~h ft.Vl '8 \\ j- ' ouhds -- ven < min fc a i -tv AG 2 ndt<, M ore than 300 rounds — you completely strip and pour tool l'ing water down to serrel and gas cylinder', and smear all parts with oil. Cleaning Before, Firing . 1st . Completely strip, dry and clean it all. I| 2nd . Dry the barrel. 3rd. As little oil as possib le to toe used. M aga^in e . If. t he magazines are not loaded, clean them and test them once a day. If thhy are loaded, empty, clean them, test and re-mi at least oncne a week. Spare Parts . Sho uld toe unpacked, cleaned and layed out for inspect- ion for the Machine Gun Inspector, and oiled and. repacked. Cleaning Afte r Dir ing . To thoroughly glean the gun alter firing hall arrmumtion the pr otreddr e should toe as follows :- 1. Strip the gun, leaving only the barrel mouthpiece, gar chamber, and radiator on the barrel- Tne gas chamber should nc be unscnev^ed unless absolutely necessary, as, if it is -constant ly removed, the thread will become worn. 2. To clean the barrel: (a)) Remove superficial fouling by means of dry flannelette. (to) If possible, run boilng water through the barrel to remove internal fouling. (c) Thoroughly dry the barrel with clean flannelette anduf inally oil the bore. ( d ) On the next and alternate days for ten days the barrel should be cleaned out with dry flannel- ette and re-oiled. To do this it is not necess- ary to strip the gun. If the barrel is in bad condition the double pull through with well o iled gauxe may be used, the subsequent treatment being the same as given above in ( c ) and( d ) . A brush may also be used on a cleaning rod when required, 3 . To clean the gas cylinder. — If the fouling is bad t. wire brush should be used om tne wooden cleaning rod. This she be followed by a piece of clean flannelette wrapped round the. v — 1A CHIDE GUNS Questions on Eirst Week Work, 1. Compare the Vickers and Lewis machine guns covering the following points: (a) How the force which operates the mechanism is obtained . (b) Method of cooling the barrel, (c) Type of magazine and number of rounds which may be fired. (d) Weights of guns. (e) How is rate of fir ing ' regulated, 2. State at least three features of the Lewis gun which makes it patft .icularly suitable for use on the airplane. 3. Into what four groups may the Lewis Machine gun be conveniently divided? 4. Name the parts included in first group, 5. " " " " " second " 6. " " " " " third " 7. Describe the barrel. 8. What three functions has the barrel mouthpiece? 9. What is the radiator made out of and the advantages gained by it? 10. Home the gas fittings. 11. Describe the receiver. 12. A - Explain how the gas chamber and regular cup is assembled. B - How is adjustment made of these parts? C - Why do we have this adjustment? Questions on Working Parts. 13. Hame the parts of the Lewis gun included in the working parts. 14. Give the names of five parts of the operating rod. 15. Describe the bolt. . What parts are assembled on the bolt? 16 - 2 - 17. Y/hat is the function of the feed operating stud? 18. What parts are assembled on the feed operating arm? 19. What is the function of the feed operating arm? 20. On what part of the gun are the stop and rebound pawls as sembled? 21* Name the parts included in the gear casing and mainspring groups • 22. Name the parts included in the guard group, 23. Y/hat is the function of the safety? Questions on Stripping. 24. (A) Y/hat tools are necessary in stripping the Lewis gun? (B) Describe each tool or guh p'art used in Stripping and state when it is used, 25. (A) Describe the stripping operation of the Lewis gun (By groups ) . (B) Describe the detail stripping of each group, step by step until the gun is completely stripped. 26. How do you reduce the tension of the mainspring (Give detail operation). LECTURE ON AMMUNITION AND AIMING - All ammunition consists of four parts, the primer, shell, powder and b ct-i. 1 * The Prime r consists of three parts, the outside casing made of soft braes which is easily dented in by the striker, the per- cussion powder and the anvil which is hard brass to resist the blow of the striker and which is made in cross shape so the fired powder ignites the shell powder . The shell is drawn brass while the powder is a smokeless powder.. The ball which is called steel clad on armor piercing ball is made of lead with a copper nickle jacket, the nickle being about 50^ of the copper nickle alloy* The function of the primer is to fire the powder, the shell to hold the primer, powder and ball, and the powder to give velocity to the ball while the ball or bullet does the work* The bullet may be solid or an explosive bullet and in the latter case the powder in an explosive bullet is only sufficient to split the bullet into pieces, the energy in the bullet doing the damage. There are four kinds of shells used, the ball catridge, blank catridge, dummy catridge and the guard catridge. The ball catridge is the one used in war, the blank for sham battles, the dummy for practice in loading and the guard catridge for home use on strike duty. The difference between the ball catridge and guard catridge are that the guard catridge uses a lead bullet instead of a steel clad arid less powder so that its velocity is 1100 feet per second instead of 2700 feet per second- The reason for having a lead bullet at a low velocity is that shooting is done at close range and it is desired that the bullet will stop when it hits into target and do no further damage as a ste-.l clad ball might kill three or four persons before it would stop. Compar ison of the 1903 and 1906 model : Catridge . Wt. of ball . Wt- of powder. Ye loo ity of ball. Barrel press.. 1903 220 grains 45 grains 2200 ft. per sec , 49,000 lbs. 1906 150 tr 51 " 2700 fi ff it 45,600 If Guard ridge. Cat- 175 n 1100 ii n 11 The advantages of the new model or Springfield rifle catridge ball is that it is pointed and has less resistance in traveling and ? s more accurate and because of the high velocity has a greater dangerous zone. Its disadvantage is because of its high velocity it cause the barrel to erode and because of this erosion the barrels are of shorter life. A very interesting fact in regards to the resistance of the air to the bullet in relation to its velocity is shown by the follow- ing diagram of the exponent and velocity curve. - 2 - The resistance R is equal to a constant bullet times the Velocity V to the power N. R " C to nature of the V n second n veloc x tj At 1100 ft. per is only ahou T 1 ~ O J. O - second n Tb i s is ,5 while at 22 or 2300 ft. per shows you the advantages of a high ity of a high to increase the ^ bullet in that the power to increase the veto* velocity bullet is not in proportion as great, as it is velocity of slot; velocity bullet a given amount* . , Before taking up aiming there is one pointy which you may be asked to make clear to some person that is why the shell is ma^e lar- ger than the bullet or ball. The reason is that m order to have enough pc wee: aniouii 'OOWUO to' give" the bullet a certain velocity it takes a certain certain space or volume in order not wh i c h o c c ur> i e s a to have a long shell which would mean an increase m the ieng m oj. the barrel the shell is made larger around so as to hold this powder and leave as much as possible of the barrel length so that the bullet will have the force of the powder behind it longer. AIMI NG- Oh S IGHTING ♦ One cf the important elements that enters into giving one supe • i o : v •ity over his enemies m ..V the use of a gun of any description, is in knowing just where his shot, is going to hit when he piesses the trigger. This superiority is gained by what vie call aiming or sighting of the gun, but this aiming includes more than just sighting through the sights at the target, it includes the setting of the . rear sight to take into account the effect of certain forces acting o n the bul let. fi: The Fc r css : . There are three forces that act on a bullet, when it is from a stationary position that cause it to go in a curved path. These forces are: the drift of the bullet to the right due to its rotation about its long axis, the drift due to wind, and drop due to gravity, I) r i ft Du e to __R ot a t ion : . - Yfnen a buTTet leaves the barrel of a rifle, it is^ given a rotation around its long axis by the rifling of the barrex an ^ this rotation of the bullet causes it to drift to the right, 1S £ r if t is taken care of to some extent by the manufacturer in se ting the sights on the gun at the time of manufacturing; that is, he sets the zero line of sight to make a small angle witn the line of fire sc that the drift to the right only directs the bullet so it hits the target. In a.eroplane fighting this drift due to rotation of the bullet is neglected as the range of firing should not^ exceed over 400 yards and at that distance witn a small caliber bullet, which travels at rate 2600 ft, per second, the drift which is not corrected for by the sights is not very appreciable and would not cause the bullet to miss its mark. (Draw diagram on board of line of sight). -3- Drift due to Win d : Here again is a force which need not be taken into con- sideration in aeroplane work, because of the short ranges which aeroplane fighting has to deal with. Although the bullet may drift a little to the right or left due to the wind, in a 400 yard range or under it would hardly be noticeable. It is useless to try and set the sight to correct for the wind because not only is drift small in 400 yards but the aviator can not judge the direction and velocity of the wind when flying due to the strong wind which hits him in the face made by the velocity of the aeroplane* A distributing fire will take into account an error made by the wind same as a. searching fire will take into account an error made in sighting or setting the sight to overcome the drop due to gravity. D is t ri bu tin g Fir e : Distributing fire means moving the gun from rightb left or left to right to cover the enemies front, which is used in aeroplane fighting to take into account the relative changes in the positions of the fighting planes. Searching Dir e : Searching fire means raising and lowering of the barrel of the rifle or gun to take into account the depth of the enemies flank, and is used to some extent in aeroplane fighting to make up for the error in estimating distance between the two machines and relative changes cf this distance. prou Due to Gravity; Before taking up the setting of the sight to take into account the action of gravity on the bullet a brief review of the ballistic properties of the machine gun will be given here in order to show what effect gravity may have on it. The bulley velocity on leaving the gun or muzzle velocity is 2600 ft. or 866 yards per second, which means that the bullet will travel, 400 yard range, which aviators have found to be the maximum range where hits may be obtained, in | of a second. Now gravity causes the bullet to drop regardless of its velocity at a certain acceleration, and the drop at any range is equal to one half of the force of gravity times the square of the time it takes the bullet to travel. S r -g- g t 2 = 16 t 2 The drop in feet of the bullets in the ranges which you will* have to deal with iu aeroplane fights are (draw diagram on board) 5-|- ft. at 4G0 yards, 2 ft. at 300 yards, 1 ft. at 200 yards, and any range less than two hundred yards you oan call it the bullet does not drop enough to make any difference- When you erter the firing period, which will last only about 6 to 8 seconds, you will not have time to change your sight to take into account the changes in the distances between the two machines so you must determine what sight you will use, that is, if you use 400 yard range sight or 4 as it is designated on sight (see figure 1) scale you will want" to aim at the level of the point you wish to hit and as the machines close as at 300 yards. If ft. lower on your target and at 200 yards 2 -g- feet lower which is, if the man is sitting, at his feet. -4- Boa r Sight : Figure 1 shews a view of the rear sight of a machine gun. It is graduated, off so that when the rider is indexed to the diff- erent figures which represent number of 100 yards the target is off, the line of fire will be raised above the line of sight so that the bullet will hit the mark. You will notice on the sight as the range increases the distance between 100 yard line marks increases because the drop is great in proportion to the square of the time* S - | g » It also means a mistake of 100 yards in estimating distance at 1000 yards is more serious than 100 yards mistake in 300 yards, or at I0C0 yards and 1100 yards the difference in drop is 4-g- ft. which 200 yards and 300 yards mean only 1 ft. Aiming, Normal S ight : We will now discuss a few points on aiming so that Then you get the machine gun to use you will take advantage of training yourselves in the proper method to use in sighting. Whether you use the peep sight or normal sight regarding results in firing can be obtained only when the same amount of the front sight is taken each time, as you can readily see from the diagrams on chart (Figures 2, 3, 4). Figure 2 represents the fine sight being used which will cause the bullet to go low and figure 4 the full sight which causes the bullet to go high. Although occasionally men will be found who ge't excellent results by using the fine sight, the average man can not, and this form of sight is not recommended. The so called full sight should never be used under any circumstances and we only show it to you for the purpose of pointing out a fault to be carefully avoided. The normal sight which you should always use is the sight shown in Figure 3 when the top of the front sight is on a line with the top and in the center of the rear sight notch and aligned upon the point of aim. M _ Linf of Sigh t _ UH£ OE. FM1E Alika vs use Normal Sight Line 2£— £' SE - Foll Sight Causes BuLLer to go High /Va '£ Normal. Fu t. L Senior Win g. You should have these notes . For each week as listed, Week 1. #8 ,set ’ #9 set #10 " #11 " Fighting in the Air. Problems in Aiming. Preparing gun for firing and cleaning. Stoppages and jams. 6 copies of sheets. Week 2. None Week 3. None Week 4. #12 set. Firing Lewis Gun. Operation of the Gun. 3 sheets copy. Week 5. #13 set. #14 set. Preparing Lewis gun for flight. Care of gun after flight. 2 sheets copy. Standard Tests in Machine Gun Training 3 sheets Copy. FIGHTING IN THE AIR. Col. L. W. B. Rees, R. F. C. & R. A., No. 32 Squadron R. F. C. These notes are based on experience of last year, so that it Is impossible to lay down any hard and fast rules, as the conditions alter so fast. The deductions are based on the experiences of many R „ F. C - Officers, to whom I am. greatly indebted* In the shooting problems the results arecnly close approxi- mations. It has been taken that the bullet does r.ot lag, due to relative speed of air and machine. COMPARISON OF DUTIES: Both the enemy and ourselves divide the machines into two distinct classes* We both have the Reconnaissance and the Fighting machines . By Reconnaissance machines I mean those that do reconnaissance proper, wireless, photography, and bombing. The Fighting machines are used for fighting only. I do not mean tosay that the Fighter does nto do his best to see what is going on, or that a Reconnaissance machine does nt sometimes fight, but their primary uses are as stated. The chief difference in these types is that the Reconnaissance machine is usually a weight carrier, so that it can not manoeuvre quickly. It may be able to "protect” itself very effectively but is so designed that the view for fighting is bad, or its method of fighting does nt lend itself to "offensive" tactics. The Fighter, on the other hand, is built solely for the purpose of attacking and bringing down the Enemy's machines, and he carries armament of an "offensive nature". The Fighting machines are used for Patrol, and for escorting the Wireless, Bombing, and Reconnaissance machines. The Enemy uses his machines differently to ourselves. His Reconnaissance machines come over our side of the Lines only at long intervals; they seldom come over far, they travel at great heights and unaccompanied. They are so fast that only our fastest machines can catch them. If fired on they immediately dive for the Lines, or for the nearest Anti-Aircraft Battery or Machine Gun, As every village near the Lines has its Machine Gun it means that the machines can dive almost anywhere so as to get a covering fire from the ground These machines very seldom turn and fight; very rightly going straight back with their information. It might be remarked here that if machines dive steeply, flames, due to excess of petrol, come out of the exhaust. The front cylinders ejlIso oil up, so that clouds of smoke come out of the exhaus as well. f the dive continues for any length of time the machine must land on account of oily or sooted plugs, and not on account of any aid which they may have obtained from the Lewis gun. Many of the Enemy Pilots are heavily handed, so that the machine turns over on landing, if the ground is at all rough. Our Reconnaissance machines, on the other hand, are continually over the enemy lines, and they go so far afield that they have to turn and fight when attacked. The Enemy Fighters never come our side of the Lines, so that our Fighters have to g o for miles to get a fight. This affects the tactics in so much as the Enemy can risk getting hit on the engine or thrugh the tank, knowing that he will suffer no mre than an ordinary forced landing. Our Fighters have to be more careful, as hits on the engine usually mean that the crew of the machine must he taken prisoners . For this reason we must make better shooting than the Enemy. We must fight to the very best advantage, and having ■ decided to open fire we must aim to disable the Enemy during the first few rounds, or at any rate during the first drum* There should be no longrange shooting, and if we can manage to disable the Enemy quickly, there will be no need to go out of action in the middle of an engagement while the drum is being changed. One will not be able to effect this without great training and much thought . TYPES OF MACHINES : The Enemy Reconnaissance machines are as a rule tractors, travelling at a speed of from 90 to 100 m.p.h. I do not think that they climb very fast, as one seldom finds them travelling very low. The Pilot sits in front of the Observer, and the Observer sits in a little barbette. This barbette permits of an all-round arc of fire, except where it is masked by the fusilage or planes. The top of the barbette is armoured, which may deflect a few bullets, but is of such shape that it would seem to be little more than useless weight. As these machines never attack, they do not usually fire ahead. They can fire at an angle of 45 degrees with the line of flight ahead. They can fire over the whole semi-circle astern. They can fire straight up, and fairly well straight down. These machines use both lead and armour-piercing bullets, fire belts of perhaps 200 rounds, and when the belt is finished they r pause quite a long time, apparently to reload. When attacking these machines on the Enemy side of the Lines, when one is creeping up apparently unobserved, the Enemy A. A. Batteries fire ahead of their own machine, and so call his attention to the danger. The Enemy Fighting machines are of four types. The first type is the sm%„ll,very quick monoplane, the small Fokker type. Apparently they are very hard to fly, as the Enemy do not seem to possess more than two or three. One can tell them at once at a distance on account of their apparent speed compared with the other machines in the sky. The Americans say that they are so fast that they can not make a forced landing across country. This may not be so, but this is the only allowable case in which a few long shots might be fired, on the chance of verifying this statement. They have a stream line in front of the propeller, which makes them appear instead of the usual monoplane For this reason they are very hard to see against the haze which always hangs over one's horizon. The Pilot sits up very high in his nacelle, so that he gets a splendid view. He has a fixed gun, and can apparently fire only straight ahead. The machines try to creep up behind their targets unseen. If seen or fired on they dive immediately and come up again after a short while. They do not as a rule accept a set battle. ihe second type is the machine a little larger than the one above* It also is a monoplane, and carries either a Pilot alone or Pilot with a Gunner. They fly in flights of four or six, and travel at a great altitude. .Then they attack a machine they dive at at firing the whole time, one after the other. They do not stop to reload, but go straight down, even if they are not fired on. They I -3 do not usually return to the attack. They fire straight ahead and straight up , ;but ! ’do J? ; t. usual ly fire astern. The third type is the large unwieldy machine, not meant to manoeuvre, hut which carries an armament heavier than can he carried in a small single-seater. The twin-engine twin-fusilage machines are of this type* These machines have everything dup- licated and a practically all-round arc of fire. They are fairly fast and are fairly good climbers* They are not as useful as would appear at first sight, because machines attacking from a flank are extremely hard to hit. The fourth type is the slow, very heavily armoured machine, which can not climb much. It carries a comparatively heavy gun -a 2-pounder, 1-^-inch machine gun, or something after that style. This type is not developed, as no machine can carry armour heavy enough to be really effective. Bullets penetrating armour carry with them fragments of the armour, so that more damage is done, on soft material (spars, tubes, etc.), by bullets which have pierced armour than by bullets which make a good clean hole. THE USE OF A FIGHTER : As I have m- itioned above, the duty of a Fighter is to put the Enemy’s machines out of action. Most of the fighting takes place on the Enemy's side of the Lines, so that it is not sufficient to make a machine land, as machines are comparatively easy to obtain-. Every effort should be made to disable the enemy Pilot, as this nearly always ensures the destruction of the machine as well, even if dual control is fitted. In any case, it prevents the Enemy using his armament effectively, and stops the machine manoeuvring. If the Pilot be taken as the target, the shots which miss the target will hit the Observer and engine, or may cause damage to the rigging. To be of real use the Pilot of a Fighter must be extremely keen sighted. I believe one can intimidate the average Enemy Pilot more by showing that he has been seen than by doing anything else. It is very hard to see machines at any distance at all, yet there must always be machines in the air within attacking dis- tance. One can often pick up the Enemy machines by finding out what the Anti-Aircraft Batteries are attacking. Machines have a habit of appearing from apparently nowhere, so that if a Pilot is not alert he is taken at a disadvantage. If an unobserved machine opens fire it takes atleast 2 seconds to pick him up and to come into action. By that time the Enemy has fired 12 rounds, which are quite enough to do serious damage. THE TARGET : When one sees a machine one is apt to think that hits any- where will be effective. One is trained to imagine that a small thing, such as a frayed cable, is certain to cause a wreck. Yet machines go up every day and return absolutely under control , but having dozens or even hundreds of holes in different places. It should be remembered that after being over the Enemy’s Lines, machines should be brought back with the greatest care. Machines are sometimes wrecked over their own aerodomes because a thoughtless pilot does a steep spiral, perhaps, not knowing that his main spars have been pierced. The only useful target to really attack is the 1 o himself- This target is very small, being of a size about 1' 6” x 1' 6", and even then shots which hit this target are n certain of putting the Pilot immediately out of action, There one must concentrate one’s attention and one s shooting small target, the Pilot, till one has attained one’ s object- If we attack a machine from directly m front or in rear the engine may cover the Pilot's body, or vice versa. This is tne minimum target which the machine can present, and any shots bitting the target do damage, but there is a lot of room round the target in which shots which do not actually strike do no damage. Now, if we imagine a machine being attacked from the side, or straight from above or below. The target which we must aim for still remains the same small one, but now the rounds, which bet ore were non-ef f ect ive , will hit the engine and Observer, and will become effective. . - This leads one to suggest that the way to attack is straign at an Enemy from above, below or from the side, keeping one’s own machine end on to him. . It is very hard, when looking at a machine in the air, zo know where the Pilot is sitting. This may sound incorrect, but if approaching from below one sees only the bottom of the Enemy’s fusilage, and as the machine is unfamiliar, the exact spot we want to hit is hidden. Even if we could hit a small practice target every time, the service target of a similar size hidden behind fabric, is quite a different proposition to tackle. With a small Fighter we should close as soon as possible, keeping end on to the Enemy, so that he will have no chance of setting any sights he may have. We are then never at a disadvan- tage, and we have the advantage of being the attacker. A machine coming at one quickly always makes one a little nervous, especially if one does not know the Pilot. With a heavy machine it is different, as a heavy Fighter can carry elaborate sighting devices. By using his very unwieldi- ness to make the machine a stable gun platform, he has more chance of concentrating his fire on the target than the little machine which is trusting to manoeuvre. Once a machine starts to manoeuvre. Once a machine starts to manoeuvre the shooting is upset till the changes in speed and direction become again constant. If we get a small Fighter against a large Fighter, if each is equipped with suitable armament, both machines should fall together. But one must remember that the small Fighter has the advantage of the initiative, that the large Fighter has a bigger area on which hits will take effect, and that it should always be possible to make the large Fighter manoeuvre by getting into a blind spot. Once the large machine manoeuvres it is at the mercy of the small one, because good shooting can not take place from a variable motion platform. ESTIMATING RELATIVE SPEEDS : When two machines meet and both manoeuvre it is very hard for either to estimate the relative speed. Take the case of two machines of equal speed revolving round a fixed point. -5- The relative motion is apparently nil, "but the actual re .ative motion at the moment of firing is practically the same as though each machine were flying straight. Enemy . 0 . Our (plan) Machine. The enemy apparently sits on the gun sights without motion, rut the maximum allowance for speed must "be made « Then, again, as both machines are banking over, it will be ery hard to estimate if there should be an allowance, because the gun .3 apparently elevated. If one machine steers a straight course at a known speed le has something to go, and can use the sights and range or speed- ’inders, which he has prepared beforehand. HMAMENT : The armament depends on the type of machine, and it should >e borne in mind that a little extra weight in machines., light machines ispecially, makes great alteration in the climb, (it does not so much if fee t the speed, ) Carry a primary and a secondary armament, i-e., a Lewis ;un and a stripped rifle or pistol. If the machine will take the weight, carry at least two guns for each Pilit and Gunner. Guns used .n pairs do not seem to jamb so frequently as guns used singly. The •ifle can be used for taking long shots, as it does not use ammunition it the same rate as the gun and is just as unlikely to hit. Take up at least five drums of ammunition per gun, as this ihould account for a Plight of machines, with a drum to spare. If rifle grenades are used, the range must be very short-, is the grenade is a very low velocity projectile. One 10-lb. bomb or a few hand grenades can be dropped on :he Enemy machines from above, and may save one losing height* Anyhow, :he Enemy will see the bomb falling, and not knowing how many are iarrded, will keep clear from below. The extra weight can always be Iropped when quick climb is necessary. Keep any gadgets inside the machine, so as not to affect iie streamline. Make certain that the use of the gadget will repay ;he loss of power due to extra weight or head resistance. When night flying carry dark glasses, so that the gun sights lay be used, even if one is within the Enemy’s searchlight. lANGE S : The ranges at which fighting takes place may vary from 400 r ards to 4 yards. It is very hard to approach a machine to within 100 rards without being seen. Hundreds of rounds are fired every day at lachines at ranges estimated at 50 yards or less without doing any iamage. At 200 yards one may expect to get hits, and I have taken ihat as the normal fighting range. I do not think that there has been i single instance in which machines have been brought down at ranges ~ iver 400 yards. -6 Thus we see that it is useless waste of ammunitioh to fire at long ranges, and that one should try arid close to within 50 yards in order to do any damage. , , Do not fire "just to show him you are there' ; fire always for effect. TRACER BULLETS: When tracer bullets came in it was thought that they would make close fighting impossible. They have not made the difference a one would expect. One reason is, that it is very hard to estimate the range in the air, just as it is at sea. The tracers burn f or a comparatively short time, so that they go out before hitting the targe This means that the bullet apparently hits, but really falls away from the target. ( elevation) When firing to a flank the tracers appear to travel in a curved path, due to the speed of the machine. (plan) If you in your younger days have ever tried to concentrate the curved trajectory of the garden hose on the nurse or gardner , you will know how hard it is to obtain effective shooting if the target dodges . Even if we can see the hits of the bullets, it is very hard to keep the proper point of impact during quick manoeuvre. If tracer bullets are fired in the centre line of the machine the observation would be much easier than if they are fired to a flank. BEE ORE ASCENT: % All Gunners and Pilots, if they use guns, should make certai themselves that the guns have been properly cleaned, oiled, and adjuste It is sometimes not realized by the mechanic in charge of guns that although on a warm day, on the ground, the gun will work perfectly, having been cleaned with "Vacuum" oil, yet, when the gun is taken and kept at a great height, the oil freezes and the gun jambs. I do not intend to go into the care and adjustment of the Lewis gun, but I must mention that any deviation from the methods laid down nearly always means a jamb. See that the implements for freeing a jamb are carried in the machine. Care in gauging and selecting cartridges makes for certain- ly of action. The adjustment of the sights with regard to the gun barrel -7- must be frequently checked, both when the gun is out, and also in the machine - Fire the gun from the machine at ranges at which it is intended to get hits, and see that the sights are aligned on the point of impact of the shots. It is also useful to fire one or two shots at a target on the ground when leaving the aerodrome, as this checks the sighting, and ensures the gun being cocked. If this is not done one will perhaps forget to cock the gun before coming into action. (Yes, it has been done . ) You can also check any adjustment you have made for allow- ing for your own speed. Think out all possible plans of attack before leaving the ground, so that no situation may be sprung on you. Always attack, as then you need not worry about means of defence. IDENTIFICATION OF MACHINES : Take great care in identifying machines. Do not take it for granted that any machine which approaches is necessarily an Enemy. The Fokker and Morane, the "Two Tail” and the Caudron, the Albatross and the Curtiss have very much the same silhouette, especially if seen from the front. All machines are becoming more and more alike, and new types are being flown every day. If one keeps between the sun and the machine under obser- vation, then his marks become visible before he can see ours* You have seen the halo which surrounds one’s shadow when it is cast on haze or clouds. The phenomenon takes place when one is on a tower, a hill or in the air. If you kAep the Enemy within the black patch in the centre of the circle he will probably not see you till you are quite :lose. To prevent being caught like this there is a service issue of tinted glass for the goggles for use in sunny weather. This glass prevents glare, and enables one to see fairly well towards the sun. The Enemy rounded cross in a white field is something similar to the Allied marks. If glasses are used for identifying machines they should not magnify more than six diameters, the vibration of the machine in- terferes with the view from glasses of greater magnification. Glasses of x 6 magnif ication are a service issue. O N SIGHTING THE ENEMY : Make certain that the gun is loaded and cocked, so that one turn one's whole attention to the Enemy. If you are flying a small Fighting Scout you can fly in any direction, including straight up for short distances, so that you can attack from anywhere you wish. A Scout should be able to get within 1000 yards (or less) of ■the Enemy without being seen, if it keeps between the Enemy and the haze over the horizon, climbing to the attack as the Fokkers do. - 8 - When you have seen the Enemy, do not hank the machine more than is absolutely necessary- At long ranges the sun shining on the planes makes the machine very visible, and at short ranges bank- ing makes one’s marks more visible- Keep end on the Enemy as long is. possible,- because that position is the most invisible, and the end-on target, is t£e smallest* If the character of a machine is doubtful* the marking on the tail usually shows up before anything else. Scouts approaching from 2000 feet above are very often -not observed. When within 800 yards of the Enemy do not fly straight unless you have reason to think that you are unobserved, because it is not known. what range and speedfinders the Enemy uses. If there. is reason to think that the Enemy has seen one, open fire before the Enemy, as one always runs the risk of being hit by stray bullets at 400 yards range. Close to within 100 yards if you can. - . ’ Having decided to open fire, go all out. This gives one' the best chance of hitting, and intimiiates the Enemy. The above statements are in places contradictory; it depends on one’s temperament what one should do. Having taken every possible precaution, trust to one’s luck as far as possible. It is well known that Napoleon considered unlucky men of no use as fighters. USEFUL ENEMY TACTICS : The single-seater Fokker tries to approach from behind. If seen or fired on he dives, to come up again a short time later. They attack in this fashion time after time. The slightly larger Fokkers dive at their target from any angle. Having fired they go straight down. Roconnaissance machines dive for the nearest A- A. Battery and fire over their tails. The heavy Fighters aim at bringing all their guns to bear. Machines seldom fly straight and make a proper attack. THE ENGAGEMENT : Open fire before the Enemy. Open fire at the shortest possible range. Open fire under the most favorable conditions. Try to disable the Enemy at once. Close as soon as you can, so as to prevent the Enemy setting his sights and taking aim. It is useless expecting to hit successfully at ranges over 400 yards. Reserve your fire till within 100 yards of the Enemy, but if discovered open fire before the Enemy. At ranges of 50 yards and under, if attacking from the flank, aim at the Enemy’s leading edge as you see it (one or other wing tip). This statement is only a guide. If one must collide go straight up, as the Enemy nearly always goes straight down. Then if one hits the Enemy one hits him with one’s undercarriage. -9- Do not collide unless "by accident. If the Enemy Pilot is dis- abled the Enemy machine may travel quite normally for a long time, so that one runs the risk of wrecking one's machine uselessly. If it is necessary to change drums, dive under a tractor, as that upsets his aim. As a rule it does not pay to follow a machine below 3000 feet. At that height the machine guns from the ground become dangerous, and if the Enemy machine is not disabled before that it will probably not be disabled at all. If no Enemy is in sight never fly straight, even on our side of the Lines. This prevents the Enemy getting the size of the machine accurately. If the size is known it is very easy to get the range at short distances, as used in fighting ih the air. Do not take anything for granted. Work out all your own deflections, etc., for your own machine. No two machines fly normally at the same speeds. Do not get put out when you find that your pet theory does not work. Machines Meeting . Machines can move at the present time in any direction the Pilot wishes. The speeds of a Lighting Scout may vary frp^m 40 m.p.h. when climbing to 100 m.p.h. on the level, and nearly 150 m.p.h, when diving.. These machines can change form one speed and direction other very quickly indeed. to any PROBLEMS IN AIMING In all these problems the velocity of the bullet is taken as 2600 ft. per sec., or 866 yds. per sec. 1. Two tractors are flying parallel to each other and in same direction. (a) If the speeds of both machines are 100 m.p.h. or 50 yds. per sec., and are 200 yds. apart, at what point would you aim to hit the pilot of the other machine? fb) If you are in a machine going at 100 m.p.h, and the enemy’s machine is only 50 m.p.h. where would you aim when you passed him ICO yds. apart? (c) If you are in a 50 m.p.k» machine and enemy passes you in 100 m.p.h. machine where would you aim if he passes you 400 ydsil off? And . (ajBirectly ai him. (b) Approx., 3 yds. or 9 ft. behind the pilot i (c) Approx. 12 yds. ih front of the pilot . 2, Two machines flying at rate 100 m a p,h. are manoeuvreing at some altitude around a fixed point gradually decreasing the distance across the circle they are describing till they are 400 yards apart. (a) At what point will you fire to hit the enemy’s pilot if you open fire when 400 yds. apart? (b) If you wait till 200 yds. apart what vail be your point of fire? Ans » (a; Approx. 46 yds. ahead. (b) Approx. 23 yds, ahead. 4. Suppose you were both flying point . . (a) Where would you airn it at 100 rn.p.h. when 200 (b) If you were both going so you would collide at a both were going at same spee yds. apaft? at different speeds? Ans « ■“fa) 4t the pilot /At ' the .pilot 5« wo machines flying parallel to each other ^oq&^sc^oth^ irections at rate 100 miles per hour and pass each ot 13 ( a) ° what * le ad^vi 11 you have if you fire when 300 yas. (b) (c) (d) (e) apart? When was sing each other? When 500 yds by each other? __ How long were machines in engagement. How far apart were your bullets spaced 4/ azine? in nag- Ans . ”Ta) Approx. (b) Tr (c) " (d) " fe) " 54 yds. ahead 11 ' TT " 34 1T 5.66 seconds 11 yds. apart PROBLEMS IN A IKING (5) 6 Give the answers to the proceeding problems if you have a sight on your gun which takes into account the speed of your machine . Answers . 1. fa) Approx. 11 yds . ahead (h) IT 3 TT TT ( c) IT 23 TT TT 2. (a) Appr ox * 23 yds. aheE'.d (b) IT 17 IT TT 3. fa) Approx , 11 yds ahead . (b) IT 11 yds. to side 4. fa) Approx, 11 yds ahead. 5. (a) Approx. 17 yds ahead fb) IT 5 TT TT (c) TT 17 TT TT A-4 SOHO OB OF i-HlIIARY AERONAUTICS- ' , 'UNIVERSITY 03' iLIINO IS ST GBP APRS AR T) JAMBS fat The cartridge guide spring Breaking fb) The deflector hag full. (c) The deflector hag working loose. Stoppages (a) (h) ( c ) Faulty ammunition and misfires. Wear on the striker post or camway groove, case hardening l/3-inch. MACHINE GUNNERS T MOTTO.- "It should he a point of honour with all gunneis co ^ P the gun firing under all circumstances. Before teaching stoppages it . is necessary to point out to the gun section that the gun will he much less liable to scop rf ; proper attention is paid to points oef ore , during, and after firing. The following in- structional kit is necessary for teaching how to remedy stoppages: - 1. No. 1 Clip. 2. No. 2 Clip. 3. Slightly bulged empty case. 4. Bulged cartridge. 5. Separate case. 6. Separation fixed on good round. 7 . Empty case 8. Empty case with one notch in its rim., 9. Empty case with two notches in its rim. The instructor should teach how to remedy ^ stoppages by first showing the positions of the cocking handle for the three classes of stoppages. He should then slowly teach the remedy for each position, seeing that every man is able to do the first remedy before proceeding to the second. When a stoppage is set up, the recruit under instruction should not be allowed to watch. The gun should be tapped off the aiming mark so that he will have to relay after he has remedied the stoppage before he fires. The position of the cocking handle should be concealed from the recruit until he is actually seat- ed at the gun and has taken his holding. When he has completed the remedy - i.e., cleared the stoppage, relaid, and fired - the instructor should check the aim. Note.- With reference to the methods of preparation of stopp- ages given in the following pages* it has always been pre- supposed that the gun is unloaded before the stoppage is set up. A- 5 PCS IT ION_pF COCKINC HAND-iE_ 1st Position.- Cocking handle forward.. Remedy of Stoppage. Try magazine (a) If fre ft) ( c ) If If change magazine, pull hack cocking handle, relay, and fire. „ , fixed, pull hack cocking handle, relay and in . many apparent mitss-fires occur, note if cocking handle comes hack too easily when remedying the stoppages. If so, unload without firing, te3{j ] and adjust return spring. Reload, relay, and i Probable Cause. ( a ) Erap t y ma g a z i n e (b) Miss- fire or space in magazine. (c) Too weak a return spring. Method of preparation with dummies. (a) Put on empty magazine with cocking handle forward. (b) Load and press the trigger. fc) Weaken return spring, load and press the trigger. 'When the ITo . 1 has done (b), the instructor says: After a few founds the gun. .stops there again. ” Preparation for Range Purposes. fa) Put on magazine with only two or three rounds in it. fb) leave an empty space in magazine. fc) Weaken return spring and place three or four dummies at intervals in the magazine. Remedy of Stoppage £. if, after trying Ifb), the gun at- ill does not fire, remove .magazine, pull back cocking handle, watch ejection opening, | and press the trigger. fa) If a round is ejected, shsnge the piston rod, reload, relay, and fire. fb) If no round is ejected, examine pawls and pawl springs, and replace where necessary. Reload, relay, and fire. Probable Cause. - fa) Broken, iv iiker. fb) Damage^, jswls, weak or 'managed pawl springs. Method of prerft' rc-ion with dummies. (a) Load aic. press the trigger. After the Ro.l has 1(b) tec instructor s vp'. . 11 dun does not fire.” done STOPPAGES (3) 1. "?r CDarat ion TOT* X* an P G OUrpOSGS. "ta , i" Tv s*- two da tv • * e s' t o ge t her in the magazine. (::) Af- wild dummies. R g m €• a y o £ S b c up a g e . xp after trying magazine rigtn c ? handle >• • r ~n i j'v 0 rna ; : a z in' ooekink handle will not come > and again pull hack cocking t r, ) j-3 the cocking hanole new comes hack with normal roe 1st one e ""pi ess he trigger, reload with new r^' 3 v" 7 * «ct i -7, i no * i? © J-gi a 7 " j 3,310 j ire o (h) If°res 1st- sn.ee is still felt when pulling hack the cookin^ handle, use the woolen handle or strap, and mi^l sharm y to the rear. See that the empty clo 1 ejc=tia and press the trigger. Reload, r e 3 ay , and fir e a % Probable cause, fa) Damaged magazine, fb) Hard extraction due to expansion of empty case, or dirt or rust in the chamber. Method of preparation with dummies,. fa) At bo oh Jo, 1 clip in front of magazine immediate- ly to the left of the ho ay , Load and press the (h) Rut a slightly bulged empty case in the chamber and press the trigger, hut magazine on post. Pre par at ion for r ang e p u rp owes. . fa) Attach Ho, 1 clip to left of magazine, (it is nor. advisable to set up chis stoppage. ) fb) Pur a slightly bulged dummy in the magazine. 2nd Position.- Cocking handle not further hack than trigger. Remedy of Stoppage, Pull hack cocking handle, if necessary using wooden handle or strap. Examine ejected roam, (a) If a bulged cartridge or a good round with the front half of a separation adhering to it, relay, and fire . (h) If a good round, unload without firing and. use the clearing plug, Reload , relay, and fire. If no clearing plug is available, immediately in- crease the tension of the return spring, reload ar press the trigger , puli back the cocking handle, when th? separation will probably come out on the nose c:. the round ejected. If so, unload, read- just, r 3 turn spring, reload, relay, and fire. Rote,- If this method fails, if is possible to remove the separation by taking off the body end using a standard 303 c 1 oar i r y; p lug . (If a succession or separation change the holt,) STOPPAGES A- 7 Pr cbab lo C aus e , ■txr abed case which comes cut . 7 0 '.l ’.iCl it (b) Load gun. Place the the chamber and ease until the extractors Preparation for range purposes. (a) Place a bulged dummy in the magazine , (b) Pile a groove round a live cartridge and place it in the magazine. 3rd Position.- Cocking handle further back than the trigger . Remedy of Stoppage. Examine ejection opening. 1. If clear pull back cocking hendl relay and fire. fa) If, when the trigger is pressed, the gun stops there again after a few rounds } pull back the cock- ing handle and apply safety catch. Take out the gas regulator, depress the safety catch and press the trigger. Replace the gas regulator with the large hole to the rear, reload, relay, and fire. (Eo, 2 manipulates the gas regulator.) (b) If, on the trigger being pressed the cocking handle gbes only s3 ightly forward and stops in the same position, remove magazine and butt, ease back cocking handle and remove the body cover and round from the cartridge opening. Replace cartridge guide spring. Reload, relay, and fire. (c) If little or no resistance is felt when pulling back the cocking handle, unload without firing, test and adjust the return spring, and if it is broken, re- place it. Reload, ielay, and fire, (d) If cocking handle cannot be -pulled right back, ease it to the roar and remove magazine, pull back cock- ing handle, put on rew magazine, relay and fire. Probable cause. 1 and (a) Hard extraction of friction in gas cylinder or moving Darts, fb) Weak or broken cartridge guide spring* (c) Weak or broken spring. (id) Damaged Magazine. A-8 STOPPAGE ; 5) 1. Put h O ! YS ' ma g n 17 c. ^ 3 ne , P 1 '-- T C Q ,*» king ban d! le three- the wa y "bn .ck an 1 ers 0 f n v»‘ vrr j v* r: V >f Cv.u v-v. -5 fa) Set up 8/ 'f. 0 r 'J , ark af *7 P r the Ho « 1 ha: 3 d< and sa V3 , T * r n Jt. _L ter a fc w or. nds , t b e g 1 m st( Ops fb) Rome ve n n rt x i ige g Cl i u 0 "0 _ ’ag , lea d , and earn hand lie TO rv- 8 X CL '« (lot l' 0 be c > OC a r -P L re quo at I (o) P ut nag 3. Z ne Oil rest . T f L iase t rr - on of -* ■» 0 J. V*. and re a T V> or ib I ,e p arts Tv 1 ) C .ta O 0 G I'm 1- ^ •‘'Ll- Ij. nudle R C} _L l - posi ■> .] n , fd) Put ma g ct 3 :Lr < rj on pest rj. ,T I y i.tt acl* Ho . 2 c 3. j_T) front o ■i - 1 i j. "0 " , sp ( p, p 7 . 1 .1 i . vrr*. ; . a ia t e , “1 r 0 n the le Full . ba .ok ; 1. /be cocking hs i far 1 0 a V I// w. > J- t w ;ers cf curing Lt.n 'd it fcrwa: Preparation for range purposes, fa) and 1. Cannot be set up. (h) Hot to be set up. ( o ) Hot to be set up. fd) Attach Uoj 2 clip to the left of the magazine, (it is not advisable to set up this stoppage. Remedy of Stoppage. 2, If empty case in chamger s pull back cocking handle and raise safety catch. Remove the magazine and push back the round in the cartridge opening. Remove empty case from chamber by means of clearing rod and examine it. Repress safety catch and ease cocking hand] e forward till the round falls into the body.. Remove if arc. press the trigger. Ifhis round must not be used;} fa) If the rim of the rim cf the emp*'~y case is cut by both extractors, reload, relay, and fire* ( b ) If its rim is cut by only one extractor or not at all, change the bolt, reload, relay, and fire. Probable cause. fa) Hard extraction, fb) One or both extractors weak or broken. Method of preparation with Rummies. (a) Load and place an empty case with in the chamber. Ease the cocking fb) Load and place an empty case with its rim in the chamber. Ease the two not he os in its rim hand 1 o for war d . one or two not he os in cock i ng handl e f o rwar d . Preparation for range purposes. fa) Cannot bo sot up. ( fb) Cannot bo sot up. j j Remedy of Stoppage, 3, -If an empty case is found in the body on the face of the bol remove magazine and butt, Rraw' back trigger guard and remove body cover. Rraw out the bolt, clear the empty case off its face, and^romove live round. Change the ejector ana re- assemble the parts with the cocking handle in the same position as when the return siring was disconnected . Reload, relay, and fire. STOPPAGES (6) Probable Cause. (3) Broken ejector. Method of preparation with dummies. (3) Load and place an empty case in the body m iront q -f -thQ ejector. Ease tne cocking h5Tr"depos~rr"and^s lightly oil the threads. Clean the cylinder with the wire brush and finish off with mop, leaving cylinder dry. After firing 500-6GQ rounds strip the gun right down. If "possible, wash the body with boiling water and thoroughly dry before oiling. All frictional parts to be smeared with oil, examining all parts during assembly. Examine return s pring ^ and oil th Test pinion pawl. Examine teeth and rack. Oil piston head . striker post and striker. Clean extra Cud s» hub Examine Cleaning barrel o Wipe out alj_ fouling with rod# Examine the barreT~~an3^"F"baaTy — corroded - black and dirty in grooves - use the double pull-through. Gauze should be on the right w ay - S shape - ano oiled . Corrosion and Erosion. Latter is due to carelessness in unnecessary wear. Leave barrel oiled. After tiring 500 rounds use boiling water, dry and oil. Use double pull through if the barrel is nickelled. Dry the barrel before firing. Care of magazine. Keep magazine in a dry place. Examine to see if" "they are distorted. Oil round centre plate and latch. ' ' A3 j >% &$: PREPARING LEWIS GUN FOR FLIGHT. . , CARE CF GUN AFTER FLIGHT Points to be Observed Before Taking a G ' ?u u p on a Machine^ fa) See that the gas regulator is at "L", by n L" is meant that the letter n L ,T should he pointing towards the hreech end oi the gun, so that the large gas hole is in use. This is essential for air work. (h) See that the handle of the fixing pin of the mounting yoke is on the right and towards the breech end of the gun. (c) See that the cartridge guide spring i s in correctly and will function as a spring. The lip of the spring may he on the wrong side of the remainder of the spring and cause it not to "give" when the cartridge comes under it. This will break the spring very quickly. (d) Feel the feed and stop pawls to see that they are work- ing freely. fe) See th&t the deflector hag is firmly and correctly fixed. If necessary have it tightened by knocking the clamp pin around with a hammer. (f) See that the fixed sight is on and firmly fixed. jfg) See that the cocking handle is securely fastened and is on the left. Pull the handle outwards at right angles to the gun. Gases have occurred of the handle not having oeen put right in and so flying out during the firing. (h) Test the mainspring to see that it is of 11-12 lhs. This is for R.F.C. purposes. It may he necessary in the air during extremely cold’ weather to reduce the spring to 9-10 lhs., in order to counterbalance a slow backward movement of the recoiling por- tion due to clogged oil, hut this low weight should not he made a rule for all times as under normal conditions the recoiling por- tion will jar on the rear of the gun, if the spring is at a lower tension than 11 lhs. (i) Work the recoiling port Lon backwards several times let- ting the handle go each time in order to ascertain that the main spring and working parts are in order. The trigger should he kept pressed during this operation. (j) If possible fire 20 rounds into the ground in order to test thoroughly the working of the; gun. This should always he possible. No special pit is necessary as a gun may he fired at an angle of 20-30 degrees and no ricochet will result providing the ground is not too stony. If it in, a, 1” board may he placed where the bullets will strike, this will prevent splinters flying around A4 Points to be Observed after the Gun has been Returned from a Pligh Plight . fa) Gun should be taken apart and thoroughly cleaned. The cylinder should not be removed until the gun has fired from 500-600 rounds. The reason for this is that the threads on the cylinder and gas chamber are very fine, and constant stripping will cause loss of gas. (Ho spares of these are provided). The only reason for removing the cylinder is to be able to clear the carbonization from the holes in the barrel and gas chamber which would check the sufficient entry of gas to cause the gun toofunction correctly. The extractors must always be removed for cleaning purposes after the gun has been fired but not at other times as they are liable to weaken* The cylinder must be cleaned -out with the wire brush and mop provided but it does not require oiling. It should be cleaned through every morning with the brush and mop. If oil is in the cylinder when firing takes place the carbon from the gases will mix with the oil and form a thick compound. This compound will "Set" quickly and if any time elapses between combats in the air it is liable to ympede the free movement of the piston and so cause the gun to stop. Examine striker post and see that it is not undtfly worn. If it is, immediately look for undue friction in the working parts or mis-shapen magazines. (b)Magazines to be emptied, examined and tested before yo being refilled. fc) Mainspring to be left at correct working weight before gun is put away, as if it is left at too great a tension it is liable to break during cold weather. During a Flight. During a flight it is a good plan to work the recoiling portions backwards and forward about 15-20 times every 10 minutes in order to free the recoiling portions in case they may be getting clogged. K3 1-3 H- p c+ CD CO 03 | A9 STANDARD TESTS IN MAC NINE- 3 [JN TRAINING PGR ROYAL FIXING oORPS. These tests have been drawn up with a view to enabling an instructor to determine if a pupil is fit at the end of a course in a squadron to undergo an advanced course in aerial firing at the llaching-Gun School, Royal Plying Corps, 75 percent of marks in. each subject should be obtained ■> i, before a pupil is considered satisfactory. TESTS 1.' Prepare Gun for Fir ing . (af Oiling).' fb) Assembling, this includes the points to be attended to b efore t akin a a gun up in a machine, (c) Testing ammunition, (d) Testing magazines. For this test all available gun spares should be upon the table. Instructor to deduct marks at his discretion. (15 marks.) . Tests of Stripping -- (a) Change cartridge guide spring. Time allowed, 10 seconds. Gun not to be stripped in this test. A dummy cartridge and spare cartridge guide spring should be by the pupil. Gun to be mounted on a tripod and ounil seated as for firing. fb) Change 1 extractor. Time allowed) 1 minute 20 sec. Spring must be at correct tension, from 11 to 12 lbs., uoon con- clusion of Phis test. A dummy cartridge anc spare extractor should le by die pupil. Gun en table. (cjf Change return spring. Time allowed, 1 minute, 30 seconds. Spring must be at correct tension upon conclusion of this test. A dummy cartridge and spare return spring, with spring tension lowered , should be near the pupil. Gun on table, "(d) Change all above. Time allowed, 2 minutes. A dummy cartridge and spares necessary to be near pupil. Gun on table. f20 marks for whole of these tests (a), fb), (c), ()d) . Points to be deducted. One point for each 5 seconds overtime i- n each of TaT) fb)', Tc ) , or (d), One point for every fault dis- covered when oup'il concludes each of (a),(b), Cc), or (&), Tests of drill in instructional room -- Changing six magazines, ix empty magazines to be by side of gun. Gun on tripod, pupil eated for firing. Magazines to be fitted to gun one by one, 'fun o be cocked, aim to be taken, trigger to be pressed, immediate ction to be gone through after pressure of trigger (without tak- ng eyes off mark) and magazines to be removed. his to be repeated until the six magazines have been gone through, ime allowed, 1 minute. (25 marks) A10 Points to be no. ted by puoil. (a) Steam lining of magazine when fitting it or removing it. fb) Noting if magazine is on correctly, (c) Immediate action with eye on object, fd) Un- loading at end of test, included in time limit. Deduction of m arks. Cue mark po be deducted for each error committed under~TaT> fb), •{ d ) and (d;« 4. Drill on range . - fa) As for 3, but if a ,22-inch Winchester automatic rifle can be obtained it should be fitted to gun so that the trigger cf the Lewis gun when pressed will release trig- ger of . 22-inch rifle. Both guns should be harmonized so that aim taken with the gunsights directs the .22- inch rifle on same mark. Magazine cf' ,22-inch rifle to have six rounds in for this test. (25 marks) Procedure as in 3 , but result cf aiming to be seen prac- tically by strike of shot on target at 10 yards. Marks to be deducted as in 3 , and also 1 mark to be deducted for every inch by which the group exceeds 4 inches in diameter. A (b) If no ,22-inch rifle is obtainable, the same tests can be carried out at 25 yards with ball ammunition, as follows: - Six magazines, each containing one round, so that it will be fed in when gun is cocked. Size of group, 4 inches. Deduct points as in (a) , but tw r c marks to be deducted for every inch above 4 inches. Time allowed in fa) or (b), 1 minute, 15 seconds. \ x 5. Mechanism. -- Pupil should be able' to give an explanation of thp working* of any part of the mechanism of the gun. Marks to bo deducted at* discretion of instructor. ’ (10 marks) Bor this test, gun and any necessary spares, such as piston rods, bolt, etc., to be on table beside gun. Also a magazine and dummies , 6. Shooting. -- Instructional practice at 25 yards does not come into tests. Glassification practice, 250 yards. -- 10 rounds ranging at target 10 feet bjf 3 feet. 100 rounds applicat ion . E'ive magazines, each containing 20 rounds, to be fired at three targets. 10 feet by 3 feet, placed side oy side. Each target to have vertical spaces marked on them, 20 Leches apart. Firer to have loaded and to be aiming. Fire to commence on command ,T Fire". Targets to be "searched” from one end to the other, in bursts of 10 rounds. Time limit, 1 minute 40 seconds; but firer is not to be told if he is exceeding this limit. Score to be signalled-- Total number of hits; spaces missed. f 15 marks) J ' ■■ :* A 11 Deduction -- Not more than 5 spaces should be missed. Two marks to be deducted for every space masse d< One mark to be deducted for every 5 seconds beyond time limit a As all squadrons are not able ( o obtain a 250 -yard range this practice j s not always possible and may be carried out at Machine Gun School. 7. Stoppages on 10 or 25 yards range. Three magazines, each containing 10 rounds. Two stoppages arranged in each magazine. (20 marks) Deductions, -- One point to be deducted for each error in application of immediate action or remedy.