Improvements in and relating to Breech Actions for Rapid Firing Guns.
Year: 1895

page_text: Date of Application, 16th Apr., 1895-Accepted, 8th June,
1895
"
Improvements in and relating to Breech Actions for Rapid
Firing Guns.
A communication from abroad by ALFRED CHRISTOPHER KOERNER, a subject
of Great Britain, residing at 21, Rue Royale, in the City of Paris, Republic
of France.
We, THE HOTCHKISS ORDNANCE COMPANY, LIMITED, of 49 Parliament
Street, London, England, 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 :---
The invention relates to improvements in guns which fire metallic ammunition,
i.e., a cartridge which serves as a gas check for the breech and containing the
percussion primer, and in which the breech action cousists of an interrupted
screw-plug, operated by a single motion of a hand lever, which unscrews the breech
plug and withdraws it, and at the same time extracts the fired cartridge case and
cocks the firing apparatus for the next shot.
1
And the object of my improvement is to provide a self-contained firing apparatus
mounted in and removable from the interrupted screw plug, and automatically
cocked by the operation of opening the gun breech; a trigger supported by the
carrier ring and which automatically locks the firing apparatus in the cocked
position, means for holding the interrupted screw plug to the carrier ring, an
extractor which ejects the cartridge shells after the gun has been fired, a safety
catch for locking the gun in case of a misfire, and other details of construction
hereinafter more fully described.
In the accompanying drawings which illustrate the invention-
Figure 1 is a longitudinal section of the gun-breech on the line 1-1 of Figure 2,
showing the breech closed and the firing apparatus snapped.
..
"
Figure 2 is a cross section of the same on the line 2-2 of Figure 1.
Figure 3 is a view of the inner face of the carrier ring with. the interrupted
screw-plug mounted therein.
Figure 4 is a rear elevation of the horse shoe piece which holds the interrupted
screw-plug to the carrier ring and the trigger device mounted thereon.
וי
Figure 5 is a longitudinal section of the firing apparatus, showing the same in
the cocked position.
Figure 6 is a side elevation of the hand-lever for operating the breech action
with the safety catch withdrawn.
Figure 7 is a similar view, with the safety catch locked.
I
Figure 8 is a section similar to Figure 1, showing the spring catch locking the
carrier ring to the breech block, when the latter has become disengaged from the
interrupted screw of the breech and is being withdrawn.
Figure 9 is a rear elevation of the carrier ring with the breach block mounted
therein and having the sear and cocking hammer removed..in order to show the
manner of securing the breech block in the ring by means oft the horse shoe piece.
Figure 10 is a view in perspective of part of the cocking hammer and the firing
pin sleeve, showing the retracting cams, and
1
44
"
Figure 11 is a view of the safety latch showing the hand lever in the locked
position
'
L
.
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" 1

page_text: In general outline the breech action consists of the cone-shaped interrupted screw
plug A, which engages in the female screw. in the gun body, its hinged carrier
ring B, the hand lever shaft C, carrying the toothed segment D which rotates the
interrupted screw, the extractor E and the percussion firing apparatus contained
in the interrupted screw A.
The cone-shaped interrupted screw plug A, which can also be made in steps of
different diameters or in any other well-known way, has its thread cut away in
three equal parts, it is held and rotated in the carrier ring B; this carrier ring is
hinged on the horizontal shaft C, which carries at the right side the hand lever F.
On the shaft C there is mounted the segment D with teeth which engage in
similar teeth cut into a projecting segment A' on the interrupted screw A. On
turning the hand lever F, and with it the horizontal shaft C, the interrupted screw
plug A is turned one-sixth of a turn and then the screw threads are disengaged
from the screw threads in the body of the gun, by continuing the motion of the
hand lever, the hinged carrier ring B is swung down, and with it the interrupted
screw, the breech is then open; as the conical shape of the screw plug obviates the
necessity of its withdrawal into the carrier ring to permit of its removal from the
gun breech. The opposite movement closes it again.
Two stops, and 61, which are formed on the lower part of the hinge of the
carrier ring bear against the body of the gun and prevent its opening further than
'necessary.
The interrupted screw plug A is held in the carrier ring B by the following
devices:
The rear end of the screw plug A which projects beyond the rear face of the
carrier ring B, has a peripheral groove a, which extends entirely around it near
the edge, thus forming a laterally projecting flange A' on the end of the screw
plug.
After the screw plug A has been seated in the carrier ring B, the crescent or
horse shoe piece T (Figures 4 and 9) is dropped into the groove a, its lower
outside face bearing against the flange A' of the screw plug and its upper inner
face bearing against the carrier ring, thus locking the two together while
permitting of the rotation of the screw plug in the act of opening the breech. A
segmental locking collar T projecting under the flange A of the screw plug and
abutting against the lower ends of the horse shoe piece T is secured to the carrier
ring B and prevents the horse shoe piece from rocking in its seat.
To prevent the interrupted screw A from turning in the carrier ring, except
when the breech is so far closed that the face of the screw threads are in line with
those of the body of the gun, there is a spring latch G fitted in the upper portion of
the carrier ring B.
The spring latch (Figures 1 and 8) consists of the screw head I having a
spindle which projects into a chamber in the carrier ring B; over the spindle i
fits the tubular cap G, extending partly over the outer rim of the interrupted
screw plug and partly against the gun body; a spring H coiled between the spindle
head and the tubular cap tends to push the latter out when not prevented by the
projection g bearing against the gun body. When, in order to open the gun, the
screw plug A is rotated in the breech to the position in which it can be withdrawn
therefrom, a recess G³ cut in the rear face of the screw plug registers with the
catch G, and as the screw plug is swung free of the breech the catch engages
therewith, locking the screw plug to the carrier ring to prevent further rotation.
In closing the breech the projection g of the catch bears, against the end of the
gun body, and the catch G is thus withdrawn from the recess in the interrupted
then this is free to turn and to be screwed entirely home by the action of the
hand lever and the toothed segments A¹ and D.
screw,
The firing apparatus is so arranged that it is entirely self contained and can be
withdrawn from the breech screw; as shown in Figures 5 and 10.
It consists of the striker pin L mounted in the sleeve P which turns freely upon
it and witn the screw plug, and having the spring M coiled around the pin-between

page_text: the flange on the striker pin and the head p of the sleeve; the cocking hammer N
mounted on the striking pin L and having two similar male cams n' n which bear
against two female cams p¹ p2 cut in the outer end of the sleeve P, and the
assembling nut O, which screws upon the end of the striker pin, and secures the
sleeve, pin, and cocking hammer together.
The head of the sleeve p thus holding these parts together fits into a suitable
cavity in the interrupted screw plug A where it is held in place by the screw
collar Q having a guide to prevent its turning in the interrupted screw plug.
T is a downwardly projecting bracket, forming part of the horse shoe piece T,
and having the pendent arms T provided with the guide grooves t" in which
run the laterally projecting guides o o of the assembling nut O, and thus prevents
the rotation of the assembling nut with the striker pin, which remain free to move
back and forth in the sleeve P and guide grooves (" ".
The action of this part of the firing apparatus is as follows: The interrupted
screw plug A being turned by the motion of the hand lever, rotates the sleeve P
with it around the striker pin L, which is prevented from turning by the guides o o
of the assembling nut and the grooves ("" or the horse shoe bracket T. As a
result, the cams pl p³ of the sleeve P pressing against the cams a³ ³ of the cocking
hammer N, drive the hammer and with it the striker pin backward into the cocked
position, whereupon it is locked by the sear R, which consists of the spring-
actuated pin R (Figure 5) located in a chamber in the bracket T, so as to engage
with the shoulder n cn the cocking hammer N when the latter is driven back.
After closing the breech and turning the breech plug A into the locked position.
the sear R is released and the firing apparatus snapped by inserting an olive-shaped
button on the end of the firing lanyard under the tail of the sear and pulling the
lanyard. The guides o o serve at the same time to keep the horse shoe piece T in
place, and this again also serves to keep the interrupted screw in the carrier ring.
The firing apparatus is shown snapped in Figure 1 and cocked in Figure 5.
It is made possible to cock the firing apparatus by hand if required, by drawing
on the projecting hook o¹ formed on the assembling screw.
The striker pin L is perforated, as shown in Figure 5 in order to allow free
escape of the gas in case of a blow back of the primer and so obviate the fouling
of the firing apparatus and consequent cause of mis-fires.
The extraction of the fired cartridge case is accomplished by the following
mechanism: The lever extractor E is hinged on the projection K of the gun-body,
the lever arm of the extractor projects upwards and under the rim of the cartridge
head and can move in a suitable mortise in the breech of the gun; at the lower end
there is a projecting tail E¹ which is struck by a projection d formed on the
carrier ring B when this is swung downwards; this causes the extractor E to
rotate around its axis K and so as to eject the fired cartridge case from the chamber
of the gun.
In order to prevent the gunner opening the breech before the discharge of the
gun when there is a misfire, or hang-fire, a safety lock is provided, which is with-
drawn automatically by the discharge of the gun and then allows the hand lever F
to be turned and the breech opened.
The safety lock (Figures 6, 7. and 11) consists of the recess W containing the
longitudinally sliding bolt. U actuated by the recoil of the gun and provided with
an off-set u which projects into the path of the nose c on the hand lever shaft. C
when the bolt is shot forward, and having a hook u¹ for withdrawing the bolt by
Land when required. The coiled spring u" between the end of the bolt and the
end of the recess W is compressed by the inertia of the bolt U on the discharge of
the gun, whereupon the hooked end of the flat spring V which forms the sear of the
belt and is secured at one end to the bottom of the recess in the rear of the bolt
engages the outer end of the bolt and locks it in position with the off-set u with-
drawn out of the path of the nose c to permit the turning of the hand lever and
opening of the breech. On closing the breech, the nose c passing over the beveled
or rounded head of the spring button v projecting through a slot in the bolt and

page_text: the recess cover into its path, presses down the button (see Figure 2) disengages
the Spring V from the bolt, allowing the latter: to fly forward and lock the land
lever until again released by the discharge of the, gun.
Figures 7 and 11 show the hand lever locked by the safety lock; Figure 6 shows
it released and in course of opening the breech.
On the discharge of the gun the safety. lock is, withdrawn by the shock of the
discharge, the hand lever. Fis, pulled backwards.by the gunner; during the first part
of the movement the interrupted screw A is caused. to rotate by means of the
toothed segments D and A', during this period of rotation the striker pin is cocked
by the action of the cams p'n' and pn and held cocked by the sear R, as soon as
the one-sixth turn of the interrupted screw A is completed the screw threads are
disengaged and the screw backed out to the amount given by the pitch. As the
carrier ring begins to swing back on the shaft C the spring catch G is enabled 'to
go forward under the action of the spring and to enter the notch G¹ in the
interrupted screw and so prevent any further rotation of the same in the carrier
ring B. On the continuation of the movement of the hand lever the whole breech
closing apparatus is swung backwards around the hinge formed by the shaft C until
the projection don the carrier ring strikes against the tail E' of the extractor E,
and so the fired cartridge case is jerked out of the gun, in the meantime the pro-
jecting lugs b and 6 of the carrier ring have brought the breech action to a stop by
striking against the bottom of the gun body. A new cartridge is now inserted into
the chamber and the breech is closed by reversing the movement of the hand lever
from backwards to forwards. The safety lock has slipped over the nose c and the
band lever is locked. The gun is now ready for firing.
To fire the gun a lanyard carrying a small steel button at its end is now inserted
under the projecting hook on the sear; on pulling the lanyard the button lifts'the
sear and the striker pin can fly forward under the action of its spring, and strikes
the primer in the cartridge and the discharge. takes place, at the saine time
the safety lock is automatically withdrawn and the breech of the gun can again be
opened..
Should it be necessary to open the breech without discharging the gun, then the
safety lock must be first withdrawn by pulling on its hook o'.
For large calibre guns 'where it is desirable to have the gun open sideways on
account of the weight of the breech, the general arrangement of the breech action
is similar to the first described, but the hinge for carrier ring &c. is placed on the
side, and the handle for opening and closing the breech is fitted to swing around in
the horizontal plane.
The sear which controls the striker is arranged so that the lanyard can be hooked
on to a. bell crank lever, the one branch of which serves to lift the sear.
'
Having now particularly described and ascertained the nature of our said. inven-
tion and in what manner the same is to be performed, we declare that what we
claim is
:
.
1. In a breech loading gun having the slotted screw system of fermeture, 'the
combination with. the carrier ring, of the screw plug seated therein and having a
circumferentially grooved rearward part projecting through said ring, and a horse-
shoe shaped collar locking into said groove and bearing against the rearward face
of the carrier ring, substantially as described.
2. In a breech loading gun having the slotted screw system of fermeture, the
combination of the carrier ring, the screw plug seated therein, a self contained and
removable firing mechanism seated in and cocked by the rotation of the screw
plug, and a sear which engages the firing mechanism when cocked, mounted in a
horse-shoe shaped collar connecting the screw plug to the carrier ring, substantially
as described.
3. In a breech-loading gun having the slotted screw system of fermeture, the
combination of the carrier ring, the screw plug scated therein, a spring-actuated
firing pin extending through an axial chamber in the screw plug, a sleeve mounted

page_text: n said axial chamber and turning with the screw plug, a retracting cam on the
firing pin, a cam on the sleeve bearing against the firing pin retracting cam, and a
non-rotating longitudinal firing pin guide exterior to the screw-plug and held
stationary by the carrier ring, whereby when the screw is rotated the pin is cocked,
substantially as described.
4. In a breech loading gun having the slotted screw system of fermeture, the
combination of the carrier ring, the screw plug seated therein, a spring actuated
firing pin extending through an axial chamber in the screw-plug, a sleeve mounted
in said axial chamber and turning with the screw plug, a retracting cain on the
firing pin, a cam on the sleeve bearing agaiust the firing pin cam, a non-rotating
longitudinal firing pin guide, and a spring actuated sear, both exterior to the screw
plug and held stationary by the carrier ring, substantially as described. .
5. In a breech loading gun having the slotted screw system of fermeture, the
combination of the carrier ring, the screw plug seated therein and having a
circumferentially grooved rearward part projecting through said ring, a horse-shoe
shaped locking collar locking into said groove and bearing against the carrier ring,
a spring actuated firing pin extending through an axial chamber in the screw plug,
a sleeve mounted in said axial chamber and turning with the screw plug, a retracting
cam on the firing-pin, a cam on the sleeve bearing against the firing-pin retracting
cam, a non-rotating longitudinal firing-pin guide and a spring actuated sear both
exterior to the screw-plug and secured to the locking collar, substantially as
described.
6. In a breech loading gun having the slotted screw system of fermeture, the
combination with the screw plug having an axial chamber, of the self-contained
removable firing apparatus consisting of the tubular firing pin L, the sleeve: P
surrounding and turning on the firing pin, and with the screw plug, the spring M
located within the sleeve between the bearing of the firing più and the head of
the sleeve, the sear shoulder n ou the firing pin, and the retracting cams n¹ n², the
cams p¹ p² on the head of the sleeve, the assembling nut O mounted on the end of
the firing pin, and the screw-collar Q mounted on the sleeve and having the guide y,
substantially as described.
7. In a breech loading gun having the slotted screw system of fermeture, the
combination of the carrier ring B, the catch located in a recess in the carrier ring
and consisting of the nut and spindle Ii and the spring actuated cap G on the
spindle projecting through the carrier ring partly over the screw-plug and the gun
body, and the screw plug A seated in the ring and having the recess G¹ on its rim
which registers with the catch when the screw plug is rotated to open the breech,
substantially as described.
8. In a breech loading gun having the slotted screw system of fermeture operated
by a single motion of a hand lever, the combination with the shaft C having the
nose c and the operating hand lever F mounted on the shaft, of the safety lock
secured to the gun body and consisting of the recess W containing the sliding bolt U
actuated by the recoil of the gun and having the off-set u in the path of the nose c,
the spring located between the rear end of the bolt and the recess, the spring
sear V attached to the case at one extremity and engaging with the bolt at the
other and having the button & projecting through the slot u in the bolt and cover
of the case into the path of the nose c, substantially as described.
t
9. In a breech-loading gun having the slotted screw system of fermeture, the
combination of the carrier ring, the screw-plug seated therein and having a
circumferentially grooved rearward part projecting through said ring, a horse-shoe
shaped collar locking into said groove and bearing against the carrier ring, and a
sear mounted on the horse-shoe shaped collar, which engages the firing mechanism
when cocked, substantially as described.
10. In a breech loading gun having the slotted screw system of fermeture, the
combination of the carrier ring, the screw-plug seated therein, and provided with
an axial chamber, a spring actuated firing pin extending through said axial chamber,
a retracting cam on the firing pin, a cam within the axial chamber rotating with the

page_text: screw-plug and bearing against the firing-pin retracting cam, and a fixed non-
rotating longitudinal firing pin guide, exterior to the screw plug and sustained by the
carrier ring, whereby, when the screw-plug is rotated, the pin is cocked, substantially
as described. :
11. In a breech loading gun having the slotted screw system of fermeture, the
combination of the carrier ring, the screw-plug seated therein and provided with an
axial chamber, a spring actuated firing pin extending through said chamber, a
retracting cam on the firing pin, a cam within the axial chamber rotating with the
screw-plug and bearing against the firing pin retracting cam, a non-rotating
longitudinal firing pin guide, and a spring actuated sear, both exterior to the screw
plug and both held stationary and supported by the carrier ring, substantially as
described.
12. In a breech loading gun having the slotted screw system of fermeture, the
combination of the carrier ring, the screw-plug-seated therein and having an axial
chamber and a circumferentially grooved rearward part projecting through said
ring, a horse-shoe shaped locking collar connecting the screw-plug to the carrier
ring, a spring-actuated firing pin extending through said axial chamber, a retracting
cam on the firing pin, a cam within the axial chamber rotating with the screw-plug
and bearing against the firing-pin retracting cam, a non-rotating longitudinal firing
pin guide and a spring actuated sear both exterior to the screw-plug and secured to
the horse-shoe shaped collar, substantially as described.
.
13. In a breech loading gun having the slotted screw system of fermeture, the
combination with the screw-plug having an axial chamber and a sleeve mounted in
and turning with the screw-plug, a spring actuated firing pin extending through said
axial chamber and sleeve, a retracting cam on the firing pin, a cam on the sleeve
bearing against the firing pin retracting cam, a non-rotating longitudinal firing pin
guide exterior to the screw-plug and sustained by the carrier-ring, whereby when
the screw is rotated; the-pin is cocked, substantially as described..
pation i
-
,
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.