SMALL ARMS.
Notes on the Automatic Pistol, Cal. 45, Model 1911.
The pistol is known as the Automatic Pistol, Cal. 45, Model 1911. By
caliber is meant the caliber of the bore. All pistols used in the
service are marked on the left side of the receiver, “United States
Property,” and on the right side with the serial number, which must be
memorized by the person to whom the pistol is issued.
It is important that every man have a thorough knowledge of the
nomenclature, care and repair, method of assembling and dismounting the
pistol as well as its use and operation.
=The principal parts= of the pistol are the _receiver, the barrel and
the slide_.
=To Dismount and Assemble the Pistol=:—Press the magazine catch and
remove the magazine. Press the plug inward, turn the barrel bushing
to the right and by easing off on the spring let the plug and spring
protrude gradually. Draw the slide to the rear until the small recess
is opposite the thumb piece of the slide stop. Press gently against
the end of the pin of the slide stop on the opposite side and remove
the slide stop. This releases the link and allows the barrel and the
slide with all its parts to be slid forward off the guide rails of the
receiver.
=To Disassemble the Slide=:—Remove the plug by turning it to the left
and withdraw the recoil spring with its guide from the rear; or remove
the recoil spring guide and withdraw the coil spring with its plug
from the front. Turn the barrel bushing to the left and withdraw it
forward from the slide. The barrel may now be withdrawn from the slide.
To remove the firing pin, press the rear end of the pin forward until
it clears the firing pin stop. Then withdraw the stop downward from
its seat, whereupon the firing pin, the firing pin spring, and the
extractor are removed by withdrawing them to the rear.
For ordinary cleaning, no further dismounting will be found necessary
and no disassembling of the receiver should be permitted except by
permission of an officer. When the interior of the pistol has been
exposed to water, or when it is desired to make repairs, the receiver
may be completely dismounted as follows:
Cock the hammer, move the safety lock to a position half way between
its upper and lower position. Press the end of the safety lock pin on
the opposite side and withdraw the safety lock. Now lower the hammer by
pressing the trigger. Push out the hammer pin and take out the hammer
and strut. Next push out the housing pin. This may require a little
extra pressure. It is the only pin pushed out by pressure from the left
side of the receiver. The main-spring housing may then be withdrawn
downward and the grip safety withdrawn to the rear. This exposes the
sear spring, which is easily removed. By pushing out the sear pin, the
sear and the disconnector are released.
The main-spring housing is disassembled by compressing the main spring,
pushing out the small main-spring cap pin, whereupon the main-spring
cap, the main spring and the housing pin retainer will come out. The
main spring may be easily compressed by using the pin of the slide stop.
[Illustration: THE AUTOMATIC PISTOL, CALIBER 45, MODEL 1911.]
[Illustration: RECEIVER, BARREL AND SLIDE.]
To remove the magazine catch, press the button inward. By means of
a small screw driver or the short leaf of the sear spring, give the
screw head of the magazine catch lock a quarter turn to the left and
remove the magazine catch. The trigger can then be withdrawn to the
rear.
The hammer strut, a small nail or the long arm of the screw driver may
be used to push out all pins except the main spring cap pin and the
ejector pin. To remove these a tack or pin may be found necessary.
To assemble the pistol proceed in the reverse order, except that the
main spring housing should be left to project about one-eighth inch. Do
not push the main-spring housing home and insert the housing pin until
after the safety lock is replaced and the hammer lowered.
=The Operation of the Pistol.=—The act of drawing back the slide in
loading cocks the hammer, compresses the recoil spring, permitting the
magazine follower to raise the upper cartridge into the path of the
slide. Upon releasing the slide, the recoil spring forces the slide
forward, carrying the first cartridge into the chamber of the barrel.
As the slide approaches its forward position, it encounters the rear
end of the barrel, forcing the latter forward. Since the front of the
barrel pivots in the barrel bushing and the rear end is free to swing
upward on the link, the rear end of the barrel is raised, causing
the locking ribs on the outside of the barrel and the inside of the
slide to engage, thus positively locking the barrel and the slide
together. The joint forward movement of the barrel and the slide (about
three-eights of an inch) is stopped when the barrel lug encounters the
pin of the slide stop.
The pistol is then ready for firing. When the hammer is cocked, the
hammer strut moves downward, compressing the main spring. The sear,
under the action of the long leaf of the sear spring, engages its nose
in the notch of the hammer. Upon pulling the trigger and pressing on
the grip safety, the sear is moved, thus releasing the hammer. The
latter then strikes the firing pin which transmits the blow to the
primer of the cartridge. The explosion of the cartridge generates
the necessary gas pressure to force the bullet through the barrel,
the initial muzzle velocity being about 800 ft. per second. The
pressure exerted to the rear against the face of the slide carries
the latter and the barrel to the rear together. But due to the link
attachment, the barrel is almost immediately swung down and unlocked
from the slide, leaving the slide to continue its movement to the
rear, thus opening the breech, cocking the hammer, extracting and
ejecting the empty cartridge and compressing the recoil spring. When
the slide reaches its rearmost position the magazine follower raises
another cartridge into the path of the slide. This cartridge is then
forced into the barrel by the forward movement of the slide as before
described.
Although it might be supposed that the downward swinging of the barrel
would affect the accuracy of the fire, this is not the case. The bullet
has gained its maximum velocity and passed out of the muzzle before the
unlocking movement between the barrel and slide commences.
When the magazine has been emptied the magazine follower is free to
press against the projection on the slide stop, thus forcing the slide
stop into the front recess of the slide, thereby locking the slide
in the open position and reminding the person firing that the empty
magazine must be replaced before firing can be continued.
Interesting Facts about the Pistol.
(a) Weight 2½ pounds. Trigger pull, about 7 pounds.
(b) Rifling, 6 grooves with left-hand twist. The drift due to the
rifling is therefore to the left, but this is more than neutralized by
the pull of the trigger when the pistol is fired from the right hand.
(c) For ranges up to 75 yards the trajectory is very flat and the drift
slight, giving the pistol great accuracy.
[Illustration: COMPONENT PARTS.]
[Illustration: COMPONENT PARTS.
1. Receiver.
2. Barrel.
3. Slide.
4. Plunger Tube.
5. Slide Stop Plunger.
6. Plunger Spring.
7. Safety-lock Plunger.
8. Slide Stop.
9. Rear Sight.
10. Front Sight.
11. Link.
12. Link Pin.
13. Barrel Bushing.
14. Recoil Spring.
15. Recoil Spring Guide.
16. Plug.
17. Extractor.
18. Ejector.
19. Ejector Pin.
20. Firing Pin.
21. Firing Pin Spring.
22. Firing Pin Stop.
23. Hammer.
24. Hammer Pin.
25. Hammer Strut.
26. Hammer Strut Pin.
27. Mainspring.
28. Mainspring Cap.
29. Mainspring Cap Pin.
30. Sear.
31. Sear Spring.
32. Sear Pin.
33. Disconnector.
34. Trigger.
35. Grip Safety.
36. Safety Lock.
37. Mainspring Housing.
38. Housing Pin.
39. Housing Pin Retainer.
40. Lanyard Loop.
41. Lanyard Loop Pin.
42. Magazine Tube. }
43. Magazine Base. }
44. Magazine Pins (2). }
45. Magazine Loop. } Magazine
46. Magazine Spring. }
47. Magazine Follower. }
48. Magazine Catch.
49. Magazine Catch Spring.
50. Magazine Catch Lock.
51. Stocks, Right and Left.
52. Stock Screws (4).
53. Screws Bushings (4).
]
(d) Beyond 250 yards the trajectory is very curved and the drift
becomes considerable. Firing is therefore very inaccurate.
(e) To hit a target at ranges over 75 yards it will be necessary to
lay on a displaced point above and to the right of target for ranges
approximately as follows:
_Vertical_ _Lateral_
_Range, Yards._ _Displacement._ _Displacement, right._
100 ½ yard ½ yard
150 1½ yards ¼ yard
200 3 yards 1 yard
250 5 yards 2 yards
(f) The striking energy of the bullet is sufficiently great to surely
disable a man by causing a dangerous wound at all ranges up to 500
yards.
(g) The pistol has been fired by experts at 25 yards, aimed fire, at
the rate of 21 shots (3 magazines) in 30 seconds. Such rapidity is,
however, not necessary or desirable in service firing. Accuracy is
always the first consideration.
Precautions.
1. Whenever the pistol is taken out of or returned to the arm rack,
also both before and after drill or other exercises with the pistol,
remove the magazine and see that it is empty. Then draw back the slide
which will eject any cartridge in the chamber. Finally look through the
bore to see that the pistol is unloaded and the bore not obstructed by
a plug or wad. Replace all parts, come to raise pistol and lower hammer.
2. Never place the trigger finger within the trigger guard until it is
intended to fire and the pistol pointed toward the target.
3. Do not carry the pistol in the holster with the hammer cocked and
the safety lock on, except in an emergency.
4. Always press the trigger with the forefinger.
5. After each shot relieve the pressure on the trigger so that the sear
may re-engage.
6. When inserting the magazine be sure that it engages the magazine
catch. Never insert the magazine by striking it smartly; always apply a
continuous push.
7. The pistol must be kept clean, free from rust and properly oiled.
8. Never disassemble the receiver except by permission of a officer.
9. In disassembling the receiver be sure that (a) the disconnector and
sear are properly assembled; (b) that the hammer is not snapped when
the pistol is partially assembled; (c) that the stocks are not removed;
(d) that no hammer is used in either assembling or disassembling.
Care and Cleaning of the Automatic Pistol.
In =cleaning= the barrel of the automatic pistol after firing proceed
as follows: Swab out the bore with soda solution to remove powder
fouling. Remove and dry with a couple of patches. Examine to see
that no patches of metal fouling are in evidence, then swab out with
the swabbing solution—a dilute metal-fouling solution. The amount of
swabbing required with the swabbing solution can be determined only
by experience assisted by the color of the flannel patches. Normally
a couple of minutes’ work is sufficient. Dry thoroughly and oil with
sperm oil.
The proper method of =oiling= a barrel is as follows: Wipe the cleaning
rod dry; select a clean patch and thoroughly saturate it with sperm or
light slushing oil, being sure that the oil has penetrated the patch;
scrub the bore with the patch, finally drawing the patch smoothly from
the muzzle to the breech, allowing the cleaning rod to turn with the
rifling. The bore will be found now to be smooth and bright so that
any subsequent rust or sweating can be easily detected by inspection.
The principles as outlined above apply equally well for the care of the
barrel of the sub-calibre cartridge.
MACHINE GUNS AND AUTOMATIC RIFLES AS EMPLOYED BY THE ARTILLERY.
The field artillery employs machine guns and automatic rifles only
defensively, either against hostile aircraft, or against enemy infantry
in case of a break-through. For this reason the tactical use of these
weapons by the artillery is considerably different from that by the
infantry, and the dispositions that must be made are adapted to
particular needs.
* * * * *
The field artillery must defend itself:
(a) On the march.
(b) In position.
(c) At the echelon (horse-lines).
Defense on the March.
1. Machine Gun.
Machine guns may be used on the march in case of surprise attack
or against low-flying aeroplanes. Fire on roads and convoys from
low-flying aeroplanes has been developed to such an extent that it is
imperative at all times for a column to be prepared to defend itself
against such attacks.
1. When a battery is in the advanced zone, one machine gun is mounted
on a special mount on the second caisson of the fifth section. This
gun is kept ready for fire at all times, the loaded belt if it is a
Browning, being kept in the loaded position. About 500 rounds Cal. 30
ammunition are carried on the caisson. The machine gunner in charge of
the gun marches with the 5th section.
A mechanic can very easily modify the special mount for the Browning,
for use against aircraft, so that it also will be adaptable for use on
the caisson.
One gun is attached to the fifth section, so that on subdivision of
the battery for action, the other gun will be with the Combat Train or
echelon, being carried in the battery wagon or the park wagon.
The second gun may be carried stored in the battery wagon or on escort
wagon. In position warfare the firing battery goes into position
usually at night. The escort wagon then goes up with tools, officers’
rolls, etc. and the machine gun with its special mount, the regular
tripod, and about 2000 rounds of ammunition. If not carried as stated,
provision must be made for carrying the gun with the firing battery.
2. Automatic Rifles.
The automatic rifles are assigned one to each section.
All eight automatic rifles should be in readiness for instant use
when on the march. They should be evenly distributed throughout the
battery, and handled by men who have had special training. At least two
magazines per gun (40 rounds) should be instantly available. While it
is difficult to bring down a plane with a machine gun or rifle, a well
directed fire will limit the action of hostile planes.
It should be borne in mind that often when in the advanced zone
friendly aeroplanes are detailed to guard a battery on the march. Great
care must be taken to make no mistakes in identifying aeroplanes.
Never shoot at a ship unless the distinctive markings on the wings are
clearly distinguished and identified. Upon subdivision for action,
the automatic rifles go with the section to which assigned. This, of
course, may be varied according to the situation.
(B.) Defense of the Position.
The machine gun emplacement should be carefully selected and
constructed. The first consideration is a good field of fire; the
second is good concealment.
Usually it is placed on a flank of the battery. Situated on the flank
of the battery, a greater field of fire is obtained for the gun.
Moreover when firing against hostile airplanes, the position of the
battery will not necessarily be disclosed. In case the battery is
shelled, the position of the machine gun on the flank renders it less
liable to be hit.
The emplacement for a machine gun at a battery position differs from
those generally built by the infantry in that it is designed primarily
for anti-aircraft shooting.
There can be no overhead cover, all protection being provided by well
constructed concealment. Camouflage must be arranged for and so placed
that it can be instantly thrown aside for firing.
The plans for close defense of the battery should include the
assignment of positions and sectors of fire for the automatic rifles.
The methods of fire and the technical points involved, in firing
against hostile airplanes, will be considered elsewhere. A sentinel
equipped with a pair of field glasses must be on duty in the
emplacement at all times. The members of the machine gun squad are
detailed for this duty by roster.
Types of Anti-Aircraft Mounts.
The Ordnance Department furnishes no anti-aircraft mount, but
improvised mounts can be easily made.
BROWNING MACHINE GUN—MODEL 1917.
The Browning Machine Gun, Model 1917, is water-cooled and is chambered
for caliber .30 U. S. Standard Rifle Ammunition. The gun is classed as
a heavy water-cooled gun, recoil operative and belt fed.
The water jacket holds about 7 pints of water and is perfectly smooth
on its interior. The steam escape tube is in the top of the water
jacket, and is made up of two tubes. They slide one upon the other, the
outer one being a little shorter than the inner one. This allows the
outer tube to slide toward either end and uncover the highest steam
escape hole. The force of recoil is utilized to perform the various
mechanical operations of feeding in the cartridges, loading, cocking,
firing the gun and ejecting the empty shells through the bottom.
The several cams of the gun make each moving part of the gun have a
positive motion.
The feed belt is made of woven fabric and has no metal parts to cause
feed jams and to add extra weight to the piece. Also the metallic
disintegrating links are used with the aeroplane gun. The fibre belt
usually contains from 250 to 500 rounds. The metallic belts can be made
to contain any number of rounds desired.
The gun has very few screws and springs. It is composed of about forty
parts which may be taken down in the field. There are a few parts which
can be assembled incorrectly and it cannot be determined that they are
so assembled until the gun is ready to be put into action. At this
point the gunner will find that the gun will not operate, therefore
great care should and must be used in the study of a quick and positive
assembling.
The weight of this gun is about 30 pounds without water. This weight
makes it necessary to use the gun on a tripod or other suitable mount.
General Data.
Weight of the gun—no water 30 lbs.
Weight of the gun filled 36.75 lbs.
Weight of the belt, 250 rounds 15.25 lbs.
Length of the barrel 24 in.
Weight of the belt, empty 7.5 oz.
Sight graduated to 2800 meters.
Rate of fire (shots per minute) 400-525.
Aimed shots per minute 120.
Calibre of bore .30 in.
Weight of bullet 150 grs.
Weight of cartridge 394 grs.
Chamber pressure lbs. per sq. in. 47,000-50,000.
Muzzle velocity (ft. per sec., theoretical) 2700.
THE BROWNING AUTOMATIC RIFLE.
General Description.
The Browning Automatic Rifle, Model of 1918, is chambered for the
United States standard ammunition. This rifle is classified as a light
automatic rifle commonly referred to as the “Light Browning.” It has
been fired 148 shots per minute, semi-automatic, while marching, and
110 shots per minute, semi-automatic, from the shoulder while in prone
position. The rates of fire, which give the best results are from 80 to
100 rounds per minute, semi-automatic marching fire and 50 to 60 shots
per minute, semi-automatic aimed fire.
Operation.
Expanding powder gases furnish the energy for the operation of the
gun. After the gun is fired and the bullet has passed the gas port in
the barrel, the live powder gases expand through the gas port into the
gas cylinder and impinge against the head of the piston. This sudden
blow forces the piston to the rear, compressing the recoil spring
and storing up energy for the return movement. The various lugs and
cams actuate the feeding, firing, extraction and ejection, and also
control the operation of the gun. The feeding is accomplished through
a magazine holding 20 or 40 rounds in double rows. It is held between
the sides of the receiver, in front of the trigger guard. This magazine
is composed of a rectangular tube and a round wire spring wound to fit
the tube. Also there is a bottom plate which slide in the bottom and
forms the rest for the spring. On top of the spring is a follower,
which forces the cartridge up against the lips of the magazine tube and
which holds it in place until stripped out by the lug on the bottom of
the bolt. The automatic action of this gun is not disturbed by holding
it in any position whatever. The magazine can be inserted while the
mechanism of the gun is in either the cocked or forward position.
All parts of the gun are designed so as to impose a minimum of shock
and strain upon them. They are also made strong enough to hold up under
the maximum amount of work that they can be made to perform. There
are few parts that can be assembled incorrectly but the gun will not
function unless these parts are assembled correctly. The dismounting
and assembling of the rifle can be accomplished without the aid of
a single tool unless the barrel and gas cylinder are removed which
necessitates the use of a special spanner wrench provided in the kit.
General Data.
Weight of gun 15 lbs. 8 oz.
Weight of Magazine, empty (20 rounds) 7 oz.
Weight of Magazine, filled (20 rounds) 1 lb. 7 oz.
Length of barrel 24 inches.
Sights graduated up to 1,600 yards.
Calibre bore 0.30 inch.
Gas port form muzzle 6 inches.
Rate of fire 500 shots p’m.
Aimed shots per minute, semi-automatic 60 shots p’m.
Weight of bullet 150 grains.
Weight of Powder 47 grains.
Weight of Cartridge (total) 395.5 grains.
Chamber pressure, pounds per square
inch 47,000 to 50,000.
Muzzle velocity 2,682 ft. p’s.
Habitual type of fire semi-automatic.
Cooling System.
It has no special cooling system or device, the barrel merely being
exposed to the air and the hand of the firer being protected on the
under side of the barrel by a large wooden forearm. Since the barrel
soon becomes very hot, care must be taken to avoid touching it during
firing or for five or ten minutes thereafter.