Improvements in Automatic Machine-guns.
Year: 1898

page_text: Date of Application, 3rd Sept., 1898-Accepted, 3rd Dec., 1898
COMPLETE SPECIFICATION (AMENDED).
Improvements in Automatic Machine-guns.
I, FRANK MILTON GARLAND, of No. 486, Elm Street, in the City of New Haven,
County of New Haven and State of Connecticut, United States of America,
Inventor, do hereby declare the nature of this invention, and in what manner the
same is to be performed to be particularly described and ascertained in and by
the following statement:-
This invention relates to a machine gun having two barrels which are so
arranged that the recoils incident to the explosions of the cartridges that are sup-
plied from a belt, are utilized to feed the cartridges, and to load and fire the
opposite barrels alternately.
The object of the invention is the production of a reliable and accurate machine
gun of this nature, having simple and durable mechanisms that can be rapidly and
safely operated automatically for feeding, loading and firing ammunition so as to
discharge projectiles individually or in quick succession.
In the gun illustrated the cartridges, which are temporarily held by spring
clips to reverse sides of a flexible belt, are by a positive feed intermittently elevated
into the case that encloses the mechanisms. As the cartridges, alternately, on
opposite sides, reach the level of the barrels, they are forced laterally from the
belt and, after being carried forward, are moved sidewise into the paths of the
breech blocks which bear the cocking levers, firing pins, sears and shell extractors.
The breech blocks are advanced alternately at the proper times and push the
cartridges into the barrels and tightly close the breeches until the cartridges have
been fired and the recoil utilized. Then the breech blocks are moved backwardly
and withdraw the exploded cartridge shells.
The recoil of an exploding cartridge in a barrel causes the backward movement
of that barrel and its breech block, and this is transmitted by connected pistons
through the medium of a confined fluid to pistons connected with the other barrel
and breech block, in such manner that the latter breech block is caused to load a
cartridge into and close the breech of its barrel. After the explosive energy has
been utilized to load the opposite barrel, the barrel that has been fired is drawn
forward by a spring and its breech block pulled further back to extract the
exploded shell and permit the placing of another cartridge in position to be loaded,
by the next forward movement of the withdrawn breech block, into the empty
barrel. The transverse movements of the cartridges discharge the exploded shells
through the sides of the case, and the belt, as its feed continues, passes out through
the top. The movement of a cartridge into the path of a breech block is accom-
plished by a transverse feed which is set in operation as the empty barrel nears
the end of its forward movement, and the movement of this transverse feed pulls
the trigger and causes the barrel that was loaded by the firing of the first barrel
to be fired and, in its turn, cause the reloading of the first barrel.
After a cartridge has been loaded into one barrel, pulling a trigger causes the

page_text: transverse feed to act and place a cartridge in position to be loaded into the empty
barrel, which action fires the loaded barrel. The firing of either barrel will feed
the cartridges and load and fire the other barrel as long as the trigger is pulled
and cartridges are supplied. The barrels may be fired individually as slowly as
desired by pulling and releasing the trigger which, if held pulled, allows the
loading and firing of the barrels alternately to continue automatically until the
supply of ammunition is exhausted.
Fig. 1 of the drawings is a plan of a gun that embodies the invention. Fig. 2
is a side elevation of this gun. Fig. 3 is a view looking toward the muzzles of
the barrels. Fig. 4 is.a plan of the outer ends of the barrels, with the spring
frame cut in section. Fig. 5 is a view of the pistol grip, showing the trigger
connection. Fig. 6 is a plan of the operating mechanisms. Fig. 7 is a vertical
section of the mechanisms. Fig. 8 is a view of the butt section of the casing,
looking from the front. Fig. 9 is a transverse section of the casing. Fig. 10 is
a longitudinal section of the butt portion of the casing. Fig. 11 is a side eleva-
tion of the belt feeding mechanism. Fig. 12 is a plan of the belt feeding
mechanism. Fig. 13 is a side elevation of the inside of a barrel frame with the
breech block closed. Fig. 14 is a similar view of the outside of a barrel frame
with the breech block opened. Fig. 15 is a plan of a barrel frame with the
breech block closed. Fig. 16 is a plan of a barrel frame with the breech block
opened. Fig. 17 is a side elevation of the breech block. Fig. 18 is an end
elevation of the breech block. Fig. 19 is a longitudinal section of the breech
block. Fig. 20 is a view of one of the buttons which may be employed to unlock
the recoil blocks. Fig. 21 is a transverse section of the casing, looking toward
the front. Fig. 22 is a vertical section of the front part of the casing. Fig 23
is a view of the trigger slides.
The barrels 1, of any caliber, extend forward side by side from the front end of
the casing 2 which encloses the operating mechanisms and to which are attached
ordinary trunions 3, shoulder rest 4, pistol grip 5 and sights 6. The casing is
made in two cylindrical sections and portions are removable in order that the
mechanisms may be uncovered for inspection. Posts 7 are secured to the front of
the casing, and to the ends of these a cross head 8 is attached. The barrels slide
through the end of the casing and through this cross head, which is perforated for
the barrels and recessed to receive collars 9 secured to the barrels. Springs 10
are coiled about the barrels and, thrusting between the collars and a yoke 11
that is adjustably joined with the fixed cross head by a bolt 12, hold the barrels
forward with a force that is regulated by the position of the yoke.
The breech ends of the barrels are secured to the heads 13 of frames 14 which
are connected by rods 15 with pistons 16 in cylinders 17 that are formed in the
butt section of the casing. Movable in guideways in the barrel frames toward
and from the breeches of the barrels are the breech blocks, 18. Levers 19 are
pivoted to the breech blocks and the long arms of these levers are connected with
recoil blocks 20 which are movable in guideways in the frames while the short
arms are attached to rods 21 that are connected with pistons 22 which move in
cylinders 23 formed in the butt section of the casing beneath the cylinders 17.
The cylinders 17 and 23 open into a common chamber 24 at the rear of the butt
section of the casing, while at the front the cylinders 17 open to a chamber 25
and the cylinders 23 open to a chamber 26. The chamber 24 has no communica-
tion with the chambers 25 and 26 but the latter are connected by a passage 27
having a port that is regulated by the valve 28, which is held from forward move-
ment by a spring 29 and from backward movement by a rod 84 that is adjustable
from the outside of the casing. These cylinders are filled with a fluid through
passages 30, and this fluid can flow in and out of the rear ends of the cylinders
freely. At the front ends the fluid can flow freely from the chamber 26 to the
chamber 25, for the valve yields to flow in that direction, but the flow in the
opposite direction may be somewhat restricted by the valve.
Levers 31 are pivoted in mortises in the barrel frames in positions to lock the

page_text: tances.
recoil blocks in the lower guideways of the frames against the backing blocks 32.
When the recoil blocks are locked against upward movement by these levers, -the
backward movements of the breech blocks and recoil blocks force back the. barrel
frames so that the pistons connected with these parts move together equal. dis-
As the frames approach the ends of their backward movements the upper
ends of the locking levers engage fingers 33 projecting from the frames 34 that
support the actuating mechanisms and are so moved as to unlock the recoil blocks.
When the barrel frames reach the end of the backward. movements, caused by the
explosive effects of the cartridges that are fired, and the recoil blocks are unlocked,
the barrels and frames are drawn forward by the springs. The forward move-
ments of the upper pistons drive the fluid in the cylinders so as to force the lower
pistons further backward, and the backward pull of these pistons causes the breech
block levers to first oscillate the recoil blocks up from the backing blocks into
the upper guideways in the frames and then to move, backward while the barrel
frames are being drawn forward. The backward movements of the recoil blocks
and the connected breech blocks open the breeches of the. barrels.
When a barrel is fired, the recoil incident to the explosion of the cartridge,
through the breech block, recoil lever and recoil block, drives the frame of that
barrel, together with the barrel, backward and the barrel frame piston and recoil
lever piston move together the same distance, for the recoil block is locked. The
effect of this is to drive the fluid from the back ends of the cylinders and rear
chamber on one side into the back ends of the cylinders on the opposite side and
this, as the barrel on that side has been drawn forward by its spring, forces the
recoil lever piston that is back on that side to move forward, carrying its con-
nected breech block and a cartridge in front of it to the breech of the barrel that
is empty.
After the explosive energy has expended itself and the breech block on the
empty side has been pushed home and becomes locked, the spring of the barrel
that was thrown back by the firing draws that barrel forward and the forward
movement of this barrel, as stated, so moves its connected piston that the fluid is
forced from the front of the upper cylinder on that side into the front of the lower
cylinder on the same side and causes the lower piston, which is connected with
the recoil lever on that side, to be moved further back and open its breech block.
In other words, when a barrel is fired its frame piston and recoil lever piston are
moved back together until the explosive energy has accomplished its work of
thrusting forward the breech block of the other barrel, then the spring of
the barrel fired draws that barrel forward and this movement causes
a flow of the fluid in such manner as to move the piston and connected
recoil block that has been unlocked backward and withdraw the breech block of
that barrel, so as to extract the exploded shell and be in position to load another
cartridge into the empty barrel.
The breech blocks have firing pins 35 that are thrust forward by springs 36,
and extracting arms 37 that are loosely placed in grooves in the upper and lower
parts. The extracting arms are arranged to travel in grooves in the barrel frames.
Cocking levers 38 are pivoted in mortises in the blocks so as to engage grooves in
the firing pins. These levers, when the breech blocks are drawn backward,
engage cocking lugs 39 secured to the casing and are oscillated so that the pins
are drawn backward and their springs made tense. When the springs are com-
pressed, sear levers 40 pivotally mounted upon the blocks engage notches and retain
the cocking levers with the springs under tension. Projecting from the inner
sides of the breech blocks are cams 41 which co-operate with the arms of the
transverse feeds.
One of the recoil piston rods may be provided with rack teeth 42, and arranged
so that it may be pushed into mesh with these is a pinion 43 having, outside of
the shell, a handle 44. By means of this pinion the piston rod and pinion may be
moved back and forth by hand.
Spring push buttons 45 may be arranged in sockets in such positions that when

page_text: forced inwardly their shanks will project into the paths of the recoil block locking
levers and so oscillate these levers as to unlock the blocks and allow the breeches
to be opened.
A pair of feed levers 46 are pivotally mounted upon the mechanism supporting
frames in positions to be oscillated by studs 59 projecting from the barrel frames.
These levers are connected by rods 47 with pawl plates 48 that carry pawls 49
which are arranged to engage teeth in, and by forward and backward movements
to intermittently advance, ratchet wheels 50. These ratchet wheels are connected
with a toothed feed wheel 51 and the shaft of this wheel bears a gear 52 that
meshes with a gear 53 meshing with a gear 54 that is in mesh with a gear 55 on
the shaft of another toothed feed wheel 56. Connected with the latter feed wheel
are ratchet wheels 57, and arranged to engage with the teeth of these is a spring
pawl 58. The feed wheels are intermittently advanced first by the movement of
one barrel frame and then by the movement of the other barrel frame. The gears
require that the feed wheels move together, and the pawl 58 prevents them from
running backward. The upper end of the pawl 58 is extended through the top of
the casing so that it may be reached from the exterior and, if it is desired, this pawl
may be moved so as to release the ratchet wheels 57 and allow them to run back-
ward.
Transverse feed arms 60 are secured to shafts mounted in the heads 13 of the
barrel frames. These shafts are provided with springs 61 under such tension
that they tend to rotate the shafts and swing the arms toward the axes of the
barrels. The front ends of the springs are connected with adjusting nuts 62
by means of which their tensions can be regulated. These arms are provided with
rolls 63 arranged in the paths of the cams 4.1 on the breech blocks so that when the
breech blocks are at the forward limits of their movements the cams force the arms
outwardly against the tensions of their springs. When the arms are forced out-
wardly, the ends of levers 64 carried in recesses in the heads of the barrel frames
are, by springs, forced beneath shoulders 65 so as to hold the arms with the springs
tense. When the barrel frames are forced backward by the explosions of the
cartridges, the projecting fingers 66 of the arms 60 pass between cartridges and
the body of the belt that has been lifted by the feed mechanism, and force the
cartridge alternately from the spring clips on opposite sides of the belt.
Swinging plates 67 are hinged to the inner faces of the barrel frames for sup-
porting the cartridges as they are forced from the belt clips, and these plates are
provided with shoulders 68 that engage the rims of the cartridge heads and,
when the barrel frames move forward, carry the cartridges with them. As the
barrel frames, together with the transverse feed arms and the supporting plates
with the cartridges, reach the forward limits to which they are pulled by the
barrel springs and the breech blocks are pulled to their extreme backward
positions, the levers 64 engage a tripping bar 69 and are oscillated so as to release
the arms and allow their springs to throw them outwardly and force the cartridges
transversely into line with the breech blocks and barrels. As the breech blocks
move forward to push the cartridges into the barrels, the cams carried by the
breech blocks again oscillate the arms and place their springs under tension.
The tripping bar 69 is mounted upon a plunger 70 that is normally held raised
by a spring 71. The lower end of this plunger is connected with a rocker arm 72
mounted on a shaft 73 supported by brackets attached to the casing. This shaft
also has a rocker arm 74 which, by a rod 75, is connected with the trigger 76
of the pistol grip 5. When the tripping bar is in its raised position, the levers 64
in their forward movement will not be engaged and oscillated, but when the
trigger is pulled and the tripping bar drawn downward, the forward movements
of the barrel frames cause such engagement with the tripping bar that the levers 64
are oscillated and release the transverse feed arms so that their springs will throw
them.
Supported side by side in front of the heads of the barrel frames are a pair of
transverse slides 77 and 78, and between portions is a spring 79 that tends to

page_text: thrust them in opposite directions. Projecting rearwardly from the end of one
slide is a stud 80, and projecting rearwardly from the upper part of the same
slide is a stud 81, while projecting from the end of the other side is a stud 82,
and projecting from the upper part of that slide is a stud 83.
When the barrels are forward and the breech blocks close the breeches, the
stud 80 extends by the side of one of the firing sears 40 and the stud 81 on the
same slide extends by the side of a shoulder on the transverse feed arm 60 on
the opposite side of the casing, while the stud 82 extends by the side of the other
firing sear and the stud 83 on the slide with the stud 82 extends by the side of a
shoulder on the other of the transverse feed arms 60. As these arms are thrown
by their springs to transversely feed cartridges, the shoulders at their upper ends
engage the studs 81 and 83 and drive the slides 77 and 78 so that the studs 80
and 82 move the scars out of engagement with the cocking levers and allow the
firing pins to be thrown by their springs for exploding the cartridges. This move-
ment of the transverse feed arm on one side so drives the trigger slide that the
firing pin on the other side is allowed to explode the cartridge in the barrel on
that side and this causes the extraction of the shell which is exploded and the
loading of a cartridge into the opposite barrel.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is :-
1. A machine gun having a casing, barrels movably supported by the casing,
pistons connected with the barrels, breech blocks movable to and from the breeches
of the barrels, pistons connected with the breech blocks, fluid cylinders for
receiving the pistons, said cylinders opening to a common chamber in front of the
pistons and to a common chamber back of the pistons, and springs arranged to
hold the barrels forward, substantially as and for the purposes described and
illustrated in the accompanying drawings.
2. A machine gun having a casing, barrels movably supported by the casing,
pistons connected with the barrels, breech blocks movable to and from the breeches
of the barrels, spring firing pins, extractor fingers, cocking levers and sears carried
by the breech blocks, pistons connected with the breech blocks, and fluid cylinders
for receiving the pistons, said cylinders opening to a common chamber in front
of the pistons and to a common chamber back of the pistons, substantially as and
for the purposes described and illustrated in the accompanying drawings.
3. A machine gun having a casing, barrels movably supported by the casing,
pistons connected with the barrels, reciprocating breech blocks that move for
portions of their travel with the barrels and for other portions of their travel
independently of the barrels, pistons connected with the breech blocks, and fluid
cylinders for receiving the pistons, said cylinders opening into a common chamber
at the front of the pistons and into a common chamber at the back of the pistons
substantially as and for the purposes described and illustrated in the accompany-
ing drawings.
4. A machine gun having a casing, barrels movably supported by the casing,
pistons connected with the barrels, reciprocating breech blocks movable to and
from the breeches of the barrels, recoil blocks loosely connected so as to have a
reciprocation with and oscillation independent of the breech blocks, pistons con-
nected with the breech blocks, and fluid cylinders for receiving the pistons,
said cylinders opening into a common chamber at the front of the pistons and into
a common chamber at the back of the pistons substantially as and for the purposes.
described and illustrated in the accompanying drawings."
5. A machine gun having a casing, barrels movably supported by the casing,
barrel frames connected with the barrels, pistons connected, with the barrel frames,
reciprocating breech blocks movable in guideways in the barrel frames to and
from the breeches of the barrels, recoil blocks connected with the breech blocks
and movable in guideways in the barrel frames, pistons connected with the breech

page_text: blocks and recoil blocks, and fluid cylinders for receiving the pistons, substan-
tially as and for the purposes described and illústrated in the accompanying
drawings.
6. A machine gun having a casing, barrels movably supported by the casing,
barrel frames connected with the barrels, pistons connected with the barrel
frames, reciprocating breech blocks movable in guideways in the frames, pistons
connected with the breech blocks, movable cartridge supports borne by the barrel
frames, and fluid cylinders for receiving the pistons, substantially as and for the
purposes described and illustrated in the accompanying drawings.
7. A machine gun having a casing, barrels movably supported by the casing,
pistons connected with the barrels, breech blocks movable to and from the breeches
of the barrels, pistons connected with the breech blocks, fluid cylinders for receiv-
ing the pistons, cams mounted upon and movable with the breech blocks, and
transverse feeds arranged to be moved by the cams, substantially as and for the
purposes described and illustrated in the accompanying drawings.
8. A machine gun having a casing, barrels movably supported by the casing,
pistons connected with the barrels, breech blocks movable to and from the breeches
of the barrels, pistons connected with the breech blocks, fluid cylinders for receiv-
ing the pistons, feed mechanisms for elevating the cartridges to the level of the
barrels, and mechanisms for feeding the cartridges transversely into line with the
barrels, substantially as and for the purposes described and illustrated in the
accompanying drawings.
9. A machine gun having a casing, barrels movably supported by the casing,
pistons connected with the barrels, breech blocks movable to and from the breeches
of the barrels, pistons connected with the breech blocks, fluid cylinders for
receiving the pistons, feed mechanisms for elevating the cartridges, mechanisms
for feeding the cartridges transversely into line with the barrels, cams on the
breech blocks for moving the transverse feeds inwardly, springs for moving the
transverse feeds outwardly, fingers for forcing the cartridges laterally from the
belt, mounted upon the transverse feeds, and trigger slides moved by the move-
ments of the transverse feeds, substantially as and for the purposes described
& illustrated in the accompanying drawings.
10. In a breech block for an automatic machine gun the combination with a
firing pin, a cocking lever adapted to engage the firing pin, and a sear arranged
to retain the lever cocked, of loosely retained extractor fingers, and a spring
thrusting the firing pin forward and the extractor fingers backward, substan-
tially as and for the purposes described and illustrated in the accompanying
drawings.
11. A transverse feed mechanism for an automatic machine gun consisting of
an arm, a finger projecting rearwardly from the arm, a shaft supporting the arm,
a spring for turning the shaft in one direction, and an adjusting device for regulat-
ing the tension of the spring, substantially as and for the purposes described and
illustrated in the accompanying drawings.
12. An elevating feed mechanism for an automatic machine gun consisting
of a pair of independently oscillating levers, pawls arranged to be oscillated by
the movements of the levers, ratchet wheels intermittently advanced first by one
and then by the other pawl, and a toothed wheel connected with and inter-
mittently advanced with the ratchet wheels, substantially as and for the purposes
described and illustrated in the accompanying drawings.
13. A firing mechanism for an automatic machine gun consisting of a pair
of transversely moving slides thrust in opposite directions by a yielding force,
breech blocks with firing pins, cocking levers and sears, studs projecting from the
slides into the paths of the sears, transversely moving arms, springs for throwing
the arms, studs projecting from the slides into the paths of the arms, levers for
retaining the arms from movement, a tripping bar in the paths of the arm levers,
and a trigger connected with the tripping bar, substantially as and for the
purposes described and illustrated in the accompanying drawings.
"

page_text: 14. In combination with the firing mechanisms of an automatic machine gun
having reciprocating barrels, trigger slides movable transversely of the barrels,
a spring for thrusting the slides from each other, studs projecting from the slides
in position to be engaged for forcing the slides against the thrust of the spring, and
studs projecting from the slides in position to engage the firing sears, substantially
as and for the purposes described and illustrated in the accompanying drawings.
15. A machine gun having a casing, barrels movably supported by the casing,
pistons connected with the barrels, breech blocks movable to and from the
breeches of the barrels, pistons connected with the breech blocks, fluid cylinders
for receiving the pistons, feeding mechanisms for elevating the cartridges, mechan-
isms for elevating the cartridges, mechanisms for moving the cartridges laterally,
mechanisms for feeding the cartridges longitudinally, transverse feeding mechan-
isms for passing the cartridges into line with the breech blocks, and a trigger
mechanism operated by the movements of the transverse feeding mechanisms,
substantially as and for the purposes described and illustrated in the accompany-
ing drawings.
FRANK MILTON GARLAND.
D. Young & Co.,
11 and 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.