Lewis Gun Gas Regulator

PLATE IV - CUS I-Aní s HKiFIVr « t Kill I1. HAI\Sl'*tSC.IMI Tílf UFIt 1U.UÍAM5U

PLATE IV

Rkckiver Group (2) Mainspring Group ($) Guard Group (5)

2-1

Receiver

2-2

Ejector Cover

2-3

Ejector

2-4

Safety

2-6

Receiver Locking Pin

9-1

Gear Casing

9-2

Gear Stop

9-3

Gear Stop Spring

lJ-4

Gear Slop Pm

9-6

Mainspring Collet Pin

9-7

Gear

9-8

Mainspring Casing

9-9

Mainspring

9-11

Mainspring Collet

5-1

Guard

5-2

Butt Latch

5-3

Butt Latch Spring

5-4

Bun Laicti Pin

5-5

Guard Side Piece (right)

5-6

Guard Side Piece (left)

5-tS

Sear

5-9

Sear Spring

5-10

Sear Pin (used also for Trigger Pin)

5-31

Trigger

Lewis Gun Parts
l1 LATE V—GUS PARTS : FRF.lí MECHAMSW, bOl.T AND EXTRACTORS

PLATE IV

Receive! Group (2) Mainspring Grouv <9) Guard Group (5)

2-1

Receiver

2-2

Ejector Cover

2-3

Ejector

2-4

Safety

2-6

Receiver Locking Pin

9-1

Gear Casing

9-2

Gear Stop

9-3

Gear Stop Spring

y-4

Gear Stop Pin

9-6

Mainspring Collet Pin

9-7

Gear

Mainspring Casing

9-9

Mainspring

9-11

Mainspring Collet

5-1

Guard

5-2

Butt Latcli

5-3

Butt Latch Spring

5-4

Butt Latch Pin

5-5

Guard Side Piece (right)

5-6

Guard Side Piece (left)

5-8

Sear

5-9

Sear Spring

5-10

Sear Pin (used also for Trigger Pin)

5-11

Feed Mechanism Group (6 and 7> Bolt (4)

6-1 Back Sight Axis Pin

6-2 Back Sight Axis Pin Washer

6-3 Back Sight Axis Pin Split Keeper

6-4 Back Sight Bed Spring

6-5 Feed Cover

6-6 Stop and Rebound Paw! Sirring

6-7 Stop Pawl

6-8 Rebound Paw!

6-V Back Sight Leaf

6-10 Back Sight Elevating Screw

6 11 Back Sight Slide

6-12 Back Sight Elevating Screw Head Spring

(>-¡3 Back Sight Elevating Screw Head

6-14 Back Sight Elevating Screw Head Pin

6-24A Cartridge Guide (assembled)

7-1 Feed Operating Arm 7-2 Feed Pawl

7-3 Feed Pawl Spring

4-1 Feed Operating Stud

4-2 Bolt

4-3 Extractor

Lewis Machine Gun Drawing
PLATE VI—BUTT STOCK, LOADING HANDLE, SPÄHE GittP ANI> ßtPOO MOUNT

PLATE VI

Butt Stock (0, Spade Grip and Magazine Fii.ung Handle (12) and Bjpod Mount (11)

1-6 A

Bait Stock (assembled)

1-1

Butt Plate

1-2

Butt Plate Screw

1-5

Butt Tang Screw

12-27A

Spade Grip (assembled)

12-49

Magazine Filling Handle

31-lA

Bipod Mount (assembled)

ASSEMBLING

The gun is assembled by reversing the operations just given for dismounting. When completely dismounted it is advisable to assemble in the following order:

a. Gas chamber in radiator.

b. Barrel into radiator and gas chamber, C. Gas chamber gland.

d. Gas cylinder.

e. Barrel mouthpiece.

f. Radiator casing, rear, g. Radiator casing, front.

h. Clamp ring, i. Gas regulator cup. j. Gas regulator key.

2. Ejector.

3. Ejector cover.

Gear, gear casing and receiver locking pin,

5. Guard (merely slipping it on receiver and up against gear to act as handle).

6. Receiver and barrel (screw barrel onto receiver).

7. Feed operating arm (pressed fully over to left).

8. Piston and rack with bolt on striker post.

9. Charging handle (replace charging handle, push it forward fully).

10. Peed cover,

II. Lock gear by raising gear case and pushing guard forward to engage it,

12. Replace butt stock.

Care should be taken :

(1) To avoid damaging the projections on the rear face of the barrel in replacing barrel and radiator in radiator casing rear locking piece.

(2) To avoid damaging the threads of the threaded parts, especially the gas chamber gland, gas cylinder and barrel mouthpiece, or allowing sand, dust or grit to get into threads.

(3) To see that the gas chamber is correctly inserted in its recess in the rajiator before the barrel is pushed home, so that the barrel loop of the gas chamber will encircle the barrel. (The barrel loop is tapered, and its smallest diameter must be toward the front end of the radiator.) Also that the harrel is turned so that the gas port is at the bottom and over the center of the gas chamber.

(4! In replacing feed cover, that the feed operating arm is over to the right.

(5) That the feed operating stud is screwed into the bolt as far as It will go and that the cam slot In the bolt Is slipped over the striker before putting piston and belt in gun.

(6) That when replacing bolt the feed operating arm is over to the left so that the feed operating stud will engage its groove,

(7) That after in'erting bolt, piston and charging handle, the charging handle is brought to the extreme forward end of its stroke before the gear casing is swung up into place and the gear engaged with the rack.

That the tension of the mainspring is corret'i — from twelve to fourteen pounds. If the tension is too low the rack will strike the butt tang too hard in opening and the action may iail to close or the gun may misfire. It it is too high the gun will fire too fait ; if much too high the gun will not open far enough to feed the next cartridge.

TO ALTER MAINSPRING TENSION

Remove hutt stock and draw guard back enough to disengage gear casing.

To increase tension hold up gear casing so as to keep gear engaged with rack and draw back charging handle. Draw down gear casing so that gear does not engage rack and push charging handle fully forward. Raise gear casing again, slide guard forward to engage it, and replace butt stock.

To decrease tension hold gear casing down so that gear is not engaged with rack and draw back charging handle. Then raise gear casing, engage gear with rack and slide guard forward to engage gear casing, which will cause the charging handle to snap forward and the action to close.

The average working tension of the mainspring is from twelve to fourteen pounds. To weigh it, engage hook of spring balance (supplied with gun) with charging handle; hold back trigger ; draw back charging handle by means of spring balance so that it is just started to the rear. Hold spring balance so as to keep charging handle at this point, and record reading.

When the gun is not about to be fired the mainspring should not be In tension.

OPERATION

TO FILL MAGAZINE WITH LOADING HANDLE

Turn magazine upside down.

Insert loading handle in socket in magazine center. This holds magazine latch out of engagement and permits rotating magazine center independently of the rest cf the magazine.

Spin magazine on loading handle to see that it is not distorted.

Rotate the magazine center and at the same time place cartridges successively between the separator pins so that their bullet ends will pass into the spiral groove in the magazine center. Do not leave an empty space between cartridges, as in firing this would cause a stoppage. The magazine holds forty-seven cartridges, and when it is filled remove loading handle and turn magazine center back until it snaps. This locks magazine.

TO FILL MAGAZINE WITH LOADING TOOL

Attach loading tool to table or other base.

Turn magazine upside down.

Slip hole in magazine center up over magazine post under loading tool until magazine latch engages post.

Spin magazine to see that it rotates freely.

Place a clip full of cartridges in top of chute and insert clip in clip ejector (at right), bullet ends to left (toward magazine center).

Press cartridges down, stripping them out of clips into chute.

Put on pressure close to clip and do not depress points.

Repeat often enough to keep chute full of cartridges.

Rotate magazine from left to right (clockwise). Cartridges will feed into magazine, if a space in magazine is skipped, rotate magazine backward past vacant space and then rotate forward again. When magazine is filled, unlatch and remove from post. Turn back magazine center until it snaps. This locks magazJne.

TO LOAD GUN

See that the charging handle is fully forward Place a magazine on the magazine post, the thumb piece of the magazine latch to the right, and press the magazine down.

Rotate it very slightly in both directions, until the magazine latch engages on magazine post.

Draw back the charging handle fully so that it is engaged and held back. This draw s back the piston and rack and perforins by hand what the gas pressure of firing does. Drawing the rack teeth back oier the gear teeth with which they are meshed rotates the gear and winds the mainspring during the entire opening movement. During the first I 1 inches of rearward travel the striker post moves baclc through the longitudinal part of its cut in the bolt and merely draws back the point of the striker from the face of the boh. The bolt itself remains in its locked position and does not move.

In the next /j of an inch of rearward travel, the striker post, driven still further rearward in the bolt, strikes with its right side the cam surface in the right side of its slot in the bolt and causes the bolt to rotate from right to left, turning the locking lugs out of their recesses in the receiver.

As soon as the bolt is unlocked, the striker post reaches 2S

the rear end of its cut in the boll, and in its further travel carries the bolt directly back with it.

The top lug of the feed operating stud, traveling in the groove In the under side of the feed operating arm, cams the feed operating arm so that it swings across the top of the receiver from right to left.

The feed pawl, acting against one of the outer projections of the magazine pan, carries the magazine around sufficiently to drive the first cartridge down into the cartridge opening in the feed operating arm by the rotation of the magazine pan and separator pins around the stationary spirally grooved center.

At this point in the leftward travel of the feed operating arm, its cartridge opening (and in it the cartridge it has just received) commences to pass under the upward projecting arms of the feed cover which carry the cartridge guide, and those arms commence to control the cartridge as soon as it leaves the magazine.

f urther leftward travel of the feed operating arm brings the cartridge under control of the cartridge guide and the downward pressure of its spring tension.

At this point the spring stud on the feed operating arm clears the stop pawl, which is then pressed forward by its spring and prevents further rotation of the magazine.

When the bolt strikes the rear end of the ejecter It drives it into its slot, thus pivoting the ejector heacl out.

Toward the end of the rearward travel of the piston the downward projection of the lower surface of the rack at the rear whose front surface forms the cocking notch rides over the nose of the sear, temporarily depressing it against the tension of the sear spring, which immediately raises it again

The rear end of the rac.k then strikes the butt tang, terminating the opening stroke.

The feed operating arm is now at the extreme left, the cartridge has been brought over the cartridge opening in the top of the receiver into which the cartridge guide presses it, the rebound pawl presses against an exterior projection of the magazine so as to prevent backward rotation, and the mainspring is fully wound up.

The mainspring now rotates the gear, whose teeth, meshed with those of the rack, drive the rack forward a trifle till the nose of the sear engages with the cocking notch in the lower edge of the rack and suspends the ope ration.

The gun is now ready to fire

TO FIRE

FULL AUTOMATIC FIRE

Press trigger and hold back. Gun will fire automatically as long as trigger is held back until magazine is empty When trigger is released gun stops firing.

SEMI-AUTOMATIC FIRE

To fire single shots press trigger and release immediately. To release quickly enough for a single shot requires some practice. Bursts of any desired length may be fired by holding back the trigger the required period of time and releasing.

When the trigger is pressed the sear is drawn down out of engagement with the notch in the rack. The rack is driven forward by the pressure of the mainspring, which unwinds, and consequently lOtates the gear, whose teeth are meshed with those of the rack. The striker post is at the rear end of the cam slot in its cut in the bolt. Its left side is pressing against the left side of the cam slot, but it 'now simply drives the bolt forward without rotating it because the bolt is prevented from rotation by the cruciform shape of the bolt-way in the receiver at this point.

The feed operating stud, carried forward with the bolt and traveling forward in its cut in the under side of the feed operating arm, cams the feed operating arm to the right.

The feed pawl slips over the projection on the rim of the magazine and engages behind it.

The spring stud on the feed operating arm presses the stup paw! back to prevent its intercepting a magazine projection

The head of the bolt now reaches the head of the ejector, which it presses back into the ejector cut, causing the tear of the ejector to be pivoted out into the bolt-way behind the bolt.

The face of the bolt now strikes the base of the cartridge which is held ready for it in the loading ramps of the receiver, and it drives the cartridge before it into the chamber.

The extractors spring over the rim as soon as the cartridge seats.

Just as the cartridge seats, the locking lugs of the bolt clear the front of the cruciform part of the bolt-way formed by their guide grooves and reach their locking recesses.

Further forward movement of the bolt is not possible. The bolt face rests against the retfr.end of the barrel and the head of the cartridge. The pressure of the mainspring which still drives the striker post forward causes the striker post, which is pressing against the left side of the cam slot in the bolt, to cam the bolt around to the right. This turns the locking lugs fully into the locking recess of the receiver.

As the bolt locking is completed the striker post enters the longitudinal front part of its cut, carries the striker against the primer of the cartridge in the chamber, and fires the cartridge.

The firing of the cartridge now develops the power for another cycle of operation.

When the bullet passes the gas port near the muzzle of the barrel, gas under high pressure is driven through the gas pun into the gas chamber and through the hole In the gas regulator cup onto the head of the piston.

This drives the piston back and produces the sameoper-

ation of parts described above where the opening stroke was made by hand, except for the disposition of the fired shell

The shell, in the grip of the extractors, is drawn back with the bolt, and is carried on the face of the bolt until the bolt strikes the rear end of the ejector, as previously described. The pivoting of the head of the' ejector, which swings sharply against the left side of the extracted shell, throws the shell out of the ejector port.

Whether the gun will fire again or wiii remain in the ready to feed " position depends upon whether or not the trigger is still held back.

If the trigger is still held back, and the sear consequently depressed, at the beginning of the closing stroke of the action the gun will continue firing.

If the trigger has been released so that the sear intercepts the cocking notch in the rack, the gun is left "ready to feed."

'the cycle of operation may be briefly summarized as follows:

VhKVl VII —MAl.AZlf.i-TOP VIEW AMI BOTTOM VIEW

PLATE VII

10-la Magazine (Assembled)

The magar.ine holds forty-seven cartridges. Instructions for loading magazine are given on Page 27.

Lewis Gun Magazine Loader
PLATE VIII—LOADING TOOL WITH MAGAZINE IS POSITION

PLATE VIII

12-30a Loading Tool (assembled)

Instructions for the use of the loading tool are given on Pages 27 and 28

backward action or G»s

Piston and rjck Strike: post .

Bolt

Feed operating arm . Magazine

ACTION

Ol'iHATES

Piston and rack.

J Mainspring and stopped i. by butt .tang.

( Unlocks bok and carries I it to the rear.

f Extracts empty shell, oper-1 ates feed o pe ra t i n g a rm, ejector, stopped by butt I tang.

| Rotates magazine, releases ■■ (right) stop pawl, cart ries cartridge.

{ Feeds cartridge onto feed [ arm and next one into j position, forces (left) I rebound pawl to rear, forward action uf

Mainspring .

Piston, rack and striker post

Bult

Feed operating arm

ACTION

OI'EKATES

Piston and striker post.

¡Bolt locked and round fired.

(Feed operating arm, c.ir-i tridge into chamber, ( ejector.

f Paivl over and behind projection, (right) stop ( paw l to the rear.

'SAFETY

TO PUT THE GUN AT "SAFE"

The gun being " ready to feed," with the charging handle back and sear engaging rack, press op'safety until its rear notch encloses the shank of the charging handle. Pull trigger, allowing the charging handle to go forward enough to engage with the under cut at the front of the slot in the safety. In this position the gun is locked at "Safe,"

WHEN AT "SAFE" TO PUT GUN IN ACTION

Draw back charging handle to cock. This frees safety.

Press down safe;y. Gun is again ready to feed," and will fire if trii?«er is pressed.

Raising the safety whet! the charging handle is forward (and the bolt is filling the ejector port) closes the action so as to prevent dust, sand, water, etc., from getting into the receiver.

The gun with charging handle forward, chamber empty, magazine on post and safety raised is practically dust and water proof, and may be carried safely and conveniently and put into action instantly by one man.

To put in action, press down safety and pull back charging handle.

CAUTION. Never let the charging handle forward by hand so that the bolt reus on a loaded cartridge in the chamber.

Remember that when magazine is on gun and charging handle is pulled to rear, gun is cocked and ready to fire. Always put it at "Safe.''

TO UNLOAD GUN

When cartridge in receiver may be fired, press over magazine latch, remove magazine and pull ihe trigger. '] liis Will fire the cartridge which was in position in the loading ramps in the receiver.

When it is necessary to unload without tiring cartridge in receiver, press over magazine latch and remove magazine, bold charging handle with left hand, press trigger with right hand and ease charging handle forward slowly so as to push cartridge from loading ramps into bolt-way in receiver.

Then pull back charging handle fully so that sear engages and raise safety. With point of bullet of another cartridge press down through loading slot in top of receiver against cartridge so that it can be removed through ejector port.

After unloading gun always snap (by drawing back charging handle to cock and pulling trigger), to make certain that gun is empty and that there is no cartridge in the receiver.

CARE and ADJUSTMENT

It i? necessary to keep continually informed of the condition of each part of the gun. Adjustment by use of tile, mi-stone or emery should be made only by an armorer. Examination should include the following points:

Barrel. Inspect the interior of barrel and chamber, the guide lips of the chamber, which project from the rear face of the barrel, and the thread on the muzzle.

Gear, Casing and Mainspring. See that gear teeth, stop and spring are not damaged, that gear case hinge pin is secure and that mainspring is not broken.

Ejector. See that it is riot damaged.

Feed Operating Arm. Observe rhat the feed pawl and feed paw l spring are properly adjusted.

Feed Cover. Notice whether the pawls and spring are damaged and whether the cartridge guide is properly assembled.

Piston, See that the piston connecting pin is not loose that the teeth and the cocking notch of the rack are not damaged, and that the working surfaces of the striker post are not burred or rough. Note whether the striker is damaged.

Bait. The edges of the cam slot should be smooLh. Any burrs or roughness should be removed by an armorer with oil-stone or line emery cloth. Test head space with maximum heading gauge. A bolt which closes over the maximum heading gauge must be changed.

Weigh each extractor by engaging hook of spring balance with extractor hook and pulling at right angles to bolt Read balance when extractor moves, [f under three pounds, exchange extractor,

POINTS BE FORK FIRING

See ti:ai bore is clear.

Weigh painspring and correct tension, it necessary ©twelve to fourteen pounds).

Verify oiling—if in doubt oil again.

Kxamine gun cases to see that all tools and spare parts are in place and thai tliey, gun and magazines are properly secured in their containers against loss or damage in transportation.

See that oil can is full.

Fiiul lest: See that charging handle moves freely, that feed operating arm moves when it does. W'eigh mainspring. Test ejection with dummy cartridge. Place empty magazine on post. Hold it with right hand and work charging handle to prove that feed mechanism rotates magazine.

POINTS DURING FIRING

Magazines should be kept in container until required. Empty magazines should be replaced in container when removed from gun, but should be refilled without preventable delay. Deformation of the rim of the magazine or the entry of dirt or grit in the bullet groove in the magazine center should he carefully guarded against, A partially emptied magazine should be replaced by a full one when fire ceases temporarily.

During temporary cessation of fire, raise safety. If rime permits, unload gun and oil bolt, striker post and piston. Weigh spring and adjust tension if necessary. Do not allow tension to drop under twelve pounds, as it might cause breakage of parts.

Jf gun misfires, wait a few seconds before drawing back charging handle.

POINTS AFTER FIRING

Unload (and snap). Relax mainspring tension.

Clean and oil barrel, cylinder, piston and gas chamber gland.

Collect any unbred cartridges among empty shells Examine, clean and oil all parts of gun as soon as practicable.

POINTS WHEN MACHINE GUN iS PLACED IN BOX

2. Exterior and working parts oily.

3. Nothing in bore.

4. Sight down.

5. Sparc parts in box.

6. Cleaning material and oil in box.

7. Mainspring released.

8. Charging handle forward and safety up.

NOTICE TO ARMORERS IN CHARGE OF LEWIS MACHINE GUNS

The efficient working of the Lewis machine gun largely depends upon the bearing surfaces between the sides of the striker post and the sides of the cam-shapcdslot in the bolt being kept perfectly smooth. In most guns, the action of the gun itself continues to keep the surface of this sliding contact properly smooth, provided the parts are kept well oiled. Sometimes, however, in the case of new guns, slight "burring" may occur and prevent the smooth working of the gun. Any such roughness or " burring " caused by wear on either of the sides of the striker post (generally on the right-hand side) or on the bearing edges of the cam-shaped slot in the bolt (generally on the left-hand side) must at once be carefully smoothed as follows;

Use either a very fine oil-stone or very fine emery cloth, or powdered emery with oil, and thus remove any rdughness and secure perfectly smooth bearing surfaces between both sides of tite striker post and both edges of the cam-shaped slot in the bolt,

Carefui attention must, however, always regularly be given to these most important bearing surfaces; but after the sides of the striker post and cam slot edges have once been carefully smoothed this roughness seldom occurs,

If either too coarse materials or too much careless force is used to smooth these surfaces, the angle of sliding contact may become slightly altered and more roughness or " burring" may be caused.

i'late ix—back sicht

PLATE IX

Back Sight

6-1 Back Sight Axis Phi

Back Sight Axis Phi Washer

6-3 Rack Sight Axis Pin Split Keeper

6-4 Back Sight Bed Spring

6-9 Back Sight Leaf

6-10 Back Sight Elevating Screw

6-11 Back Sight Slide

6-13 Back Sight Elevating Screw Head

12-37

12-51

12-55

12-50

I3-5A

12-54

12-54

KAt h x -AtCKSStmiiS

PLATE X

Accessories

3 2-5 A Shell Extractor (assembled)

12-1 A Charging Handle Extension (assembled)

12-50 Barrel Mouthpiece Spanner

12-24A Barrel Cleaning Rod (assembled)

12-51 Cylinder Cleaning Brush (wire)

12-52 Cylinder Cleaning Mop

12-53 Barrel Cleaning Brush (bristle)

32-54 Oil Can

12-55 Spring Balance

Lewis Gun Spade Grip

CLEANING and OILING

The gun must be cleaned thoroughly as soon as possible after tiring. Barrel should be swabbed with oil or a nitro-solvent as soon as gun is unloaded. The gas regulator cup, gas chamber and gland, gas cylinder and piston should also be temporarily cleaned and oiled at once.

To Clean Barrel. Introduce cleaning rod at tiuzzie, pursuing in other respects the same methods prescribed and using the cleaning solutions issued for cleaning the U. S. magazine rifle, model 1906. Cleaning with nitro-solvent on patches of cloth does not require dismounting the gun. The charging handle may merely be drawn back until the sear engages the rack.

To use the ammonia solution for metal fouling, the barrel must be taken off the receiver, the radiator casings, front and rear, must be removed, and the gas chamber gland must be taken out. The chamber and the gas port must be securely corked with suitable rubber corks and ashort length of rubber tubing must be slipped over the muzzle of the barrel so that the ammonia solution will stand in the tube well above the end of the muzzle.

The greatest care must be taken not to bend or injure the guide lips of the chamber at the rear end of the barrel. Cleaning the barrel from the muzzle is directed so as to reduce as far as possible the danger of injuring these projections.

Cleaning the barrel should be repeated every day for several days after the gun has been fired and until the acids driven into the pores of the steel by the pressures of firing have been completely neutralized. The ammonia metal fouling solution neutralizes acid residue at one application.

Russian Machine Gun Plate Magazine
PLATE XIÍ MEW JHOUING I'KUI'ER METHOD OF M.AC1HG MAGAZINE OS MAL.A/1.NE POST

To Clean Gas Cylinder. For temporary cleaning, cylinder need not lie taken out of gun. Withdraw bolt and piston and insert cylinder cleaning rod through piston hole in receiver. Clean first with a wire brush and gasoline and then with the mop and oil.

If gun is left uncleaned after firing, LhreaiS may seize and m;ike cylinder hard to unscrew. Thread should then be soaked with oil before trying to unscrew. Push rack well into squa ed portion of cylinder before unscrewing—if not in tar enough, cylind?r may be split at rear end,

Ti Clean Action Parts. Soak off hard fouling with gasoline or oil. Parts cleaned with gasoline should be dried and oiled afterivard. Additional oihng of moving parts, the surfaces against which they bear and parts through which gas passes ts necessary to prevent friction and clogging as well as rust. The striker post and the inside of the boil should always be kept well oiled. Whenever any time is available during firing it is advisable to oil them again. The feed operating stud, piston and rack should also be oiled frequently, Magazine latch and outer edge of cartridge spacer ling should be oiled lightly. AM screw threads Should he kept well oiled to prevent their slicking fuirn rust.

lie liberal in use of oil,

A good grade of high flash oil should be used.

POSITION Of CHARGING HANDLE

First Position—Charging Handle ftr*ward*

, Try magazine. If it rotates freely to left, change it.

If magazine is fixed, pull back charging handle and continue firing»

li 2 fails, change magazine.

J f stoppage recurs, examine feed pawl and stop and rebound pawls. If feed pawl is broken magazine will not rotate.

If 3 fails and trigger being pressed gun does not fire, examine mainspring. If light, j tighten ; if broken, change gear I and casing. If mainspring all right, change piston and rack, (k If charging handle will not comeback, vtse charging handle extension or belt. If stoppage , recurs, examine chamber,

PROBABLE CAUSE

Kmpty magazine, no round in chamber,

(c) Insufficient rotation of magazine.

Damaged magazine.

Damaged feed pawl or slop or rebound pawl.

(j) Weak or broken mainspring,

{') Broken or damaged striker.

Hard extraction. <3> Expansion of empty case, (b) Grit or rust in chamber.

PREPARATION FOK INSTRUCTION

Kmpty magazine on post.

Charging handle forward on range. Leave space in magazine.

On Range.

Put damaged dummy in chamber, pull trigger and put full magazine on post.

Second Position^ Less than a cartridge length from forward position.

Third Position—More than 3 inches back.

Use charging handle extension or double pull through ami pull back handle. Exam hi., round ejected, if—

(a) Damaged or too large louml, continue Hring.

(b) If correct, take off magazine, insert shell extractor into chamber and push home with bolt and withdraw with front portion of separated case,

! (c) Separated case is telescoped I on to cartridge, continue I firing, N. B.—In nine cases out of ten the next cartridge pulls out the separation, (d) If separation recurs shortiy, change bolt.

1. Examine ejection opening; if there is no obstruction, put! back charging handle, continue firing«

If recurs, take out gas regulator cupt remove magazine and fire one round j replace regulator cup targe hole to rear. Clean out gas cylinder, oil

Damaged round.

Separated case in chamber.

Separated case te'e-scoped on to next cartridge.

Too sharp extract-ois, which cut cartridge case at base.

lioit has not gone back far enough to get behind base of cartridge. (a> Friction in gas cylinder, (h) Hard extrac-

Kilea groove around cartridge case I inch from base.

Ditto 1 inch from shoulder.

STOPPAGE S—Continued

POSITION OF CHARGING HANDLE

Third Position—Continued.

working parts; if any roughness on striker post or cam slot in bolt, change them.

2. if on pulling back handle there is little or no resistance, if main spring is light, tighten; tf broken, change.

3. If an empty case is in chamber or ejection opening, take off magazine, draw back charging handle, and unload without firing.

If empty case is in chamber, force out with cleaning ro«J from muzzle end. If there are no signs of extractors, or only one extractor gripping it, change bolt; otherwise continue firing.

4. H stoppage recurs, examine extractor, exchange whichever is faulty.

probable cause preparation for instruction

Weak or broken < Oh Range. mainspring, i Weaken mainspring

(!>) Hard extraction. 1 Place empty case

<c) If empty case is ¡ in receiver, weak extractors t broken ejector.

chamber. Magazine on post and pull trigger

Tlurd Position— tinued.

5. if charging handle cannot be moved, remove magazint. if charging handle iiits forward, change magazine.

G. If on removing magazine, charging handle remains in position as before-— <a) Help cartridge into correct position on feed way. <b) Test cartridge guide spring. <c) Test mainspring.

(a) Damaged magazine jammed.

(b) Magazine not pro perl yon m sga -zine post.

(c) Broken maga zine catch spring.

(d> Broken or damaged magazine spacer ring causing it to jam.

(a) Weak or broken cartridge guide spring.

tb) Too weak mainspring.

On Range. Do not push magazine p r o p e i \ y home.

U) The tension of the main spring can easily be told by puiling back the charging handle. If the main spring is broken, the collet pin wilt be "out,"

Note—If the gun continues to fire after the trigger is released, push forward trigger with hand on right side.

This will be caused by broken or weak, spring, or damaged seat

SEQUENCE OF IMMEDIATE ACTION

Lewis Machine Gun

No 1 POSITION

(Charging Handle Forward) Try Magazine

¡F FREE TO ROTATE Change it

Reload, relay and fire

IF GUN DOES NOT FIRE

Pull C, H. Watch ejection opening

IF GUN FIRES SINGLE SHOTS Examine gas regulator

IF CARTRIDGE IS EJECTED Examin« primer

IF NO CARTRIDGE IS

EJECTED Examine feed mtfcrus'n Repair if necessary

ÎF FIXED (will not totale) Pull charging handle

IF CHARGING fl. WILL NOT GO BACK Remove mag a line 1 .

IF C H. THEN COMES EASILY Put on new magazine Reload, relay nil

IF PRIMER NOT STRUCK

Chang* piston and rack, reload, relay ami tire

No. 2 POSITION

U hargmg Handle between thumb- piece of safety and forward posit ion)

FORCE HACK CHARGING HANDLE

IF STOPPAGE RECURS Take out gas* regulator, fire a shot. Insert with large hole to rear. Clean and oil

No. 3 POSITION

(Chaining Handle behind thumb-pi«« of safety.) Examine ejection opening

IF CASE ÏN BOLT-WAY Examine ejector Replace if necessary

IF CHAMBER OBSTRUCTED Puil C. H. Raise safety, remove magazine, clean and examine rim of cartridge

IF C. H. DOES NOT COME BACK Change magazine, reload, relay and fire

IF RIM CUT IN TWO PLACES Reload, relay and fire

IF RIM NOT CUT Change bolt

IP C. H. DOES NOT GO FORWARD Change Sear casing (complete)

IF C. H. STARTS FORWARD

AND STICKS Puil C. H. Raise safety Remove magazine Inspect cartridge guide Replace if necessary

Was this article helpful?

0 0

Post a comment