IMPROVEMENTS IN BREECH-LOADING SMALL ARMS
Year: 1881

page_text: LETTERS PATENT to John Field Swinburn, of Birmingham, in the County
of Warwick, Gun Manufacturer, for an Invention of "IMPROVEMENTS IN
BREECH-LOADING SMALL ARMS."
PROVISIONAL SPECIFICATION left by the said John Field Swinburn at
the Office of the Commissioners of Patents on the 7th February 1881.
JOHN FIELD SWINBURN, of Birmingham, in the County of Warwick, Gun
Manufacturer. "IMPROVEMENTS IN BREECH LOADING SMALL ARMS."
My Invention has reference to breech loading small arms in which the breech
ends of the barrels are raised from the break off for charging and shut and locked
down against the break off during discharge, and consists of the arrangements or
combinations of parts, hereinafter described, for cocking the internal hammers
of the said small arms and for preventing the accidental discharge of the said
arms.
For convenience of description I will first describe the safety apparatus or the
mechanism for preventing the accidental discharge of the arm or gun. Or the
fixed axis on which the hammer turns is a lever, the front end of which is situated
immediately over the projecting lower end of the lump on the barrel. The raising
of the breech end of the barrel causes the said lump to lift the said lever. The
rear end of the said lever engages with the front end of a second lever, and the
rear end of the second lever is situated under an incline in a spring sliding bolt
in the stock of the gun. When this bolt is in its normal or shot position its front
end is situated immediately over the rear end of the trigger and sear, and prevents
the rising of the trigger and sear, and consequently prevents the discharge of the
gun. This spring bolt may either be withdrawn by the pressure of the hand in
grasping the gun for firing, the fingers pressing upon a lever which withdraws the
sliding bolt; or the said bolt may be withdrawn by pressing forward a thumb
plate on the upper side of the stock. The said thumb plate is situated on the
top of a nearly vertical lever, the lower end of which is connected to the spring
bolt.
When the said thumb plate is pressed towards the muzzle of the gun, its lower
end, moving in an opposite direction, withdraws the sliding bolt from over the
trigger and sear, and the gun may be discharged.

page_text: The cocking of the gun is effected by the rising motion of the breech end of the
barrel in the following manner :-
The first named lever has on its front end a fixed cross pin projecting on both
sides of the lever in a double barrel gun, but projecting on one side only in case of
a single barrel gun.
On the breast of the hammer is an arm situated immediately over and bearing
upon the cross pin on the said first named lever. When the breech end of the
barrel is raised and the lump operates on the first named lever to bring the safety
apparatus into action, the said pin lifts the arm on the breast of the hammer and
throws the hammer back into its cocked position, in which position it is retained
by the bent and sear, and the gun is ready for discharge.
Or the cocking of the gun may be effected by the rising of the lump on the
barrel without the intervention of the first named lever of the safety mechanism.
In this case the breast of the hammer carries on its inner side or face a pin or
projection, the inner end of which is situated immediately over the projecting lower
end of the lump. On the raising of the barrel the lump lifts the pin or projection
on the inner side or face of the breast of the hammer, and thereby throws back
the hammer, which is retained in its cocked position by the sear and bent.
My improvements are applicable both to single and doubled barrelled guns and
pistols of the kind described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Field Swinburn in the Great Seal Patent Office on the
29th July 1881.
JOHN FIELD SWINBURN, of Birmingham, in the County of Warwick, Gun
Manufacturer. "IMPROVEMENTS IN BREECH LOADING SMALL ARMS."
My Invention has reference to breech loading small arms in which the breech
ends of the barrels are raised from the break off for charging and shut and locked
down against the break off during discharge, and consists of the arrangements or
combinations of parts, hereinafter described, for cocking the hammers of the said
small arms and for preventing the accidental discharge of the said arms.
For convenience of description I will first describe the safety apparatus or the
mechanism for preventing the accidental discharge of the arm or gun.
On the fixed axis on which the hammer turns is a lever, the front end of which
is situated immediately over the projecting lower end of the lump on the barrel.
The raising of the breech end of the barrel causes the said lump to lift the said
lever. The rear end of the said lever engages with the front end of a second lever,
and the rear end of the second lever is situated under an incline on a sliding bolt
in the stock of the gun. When this bolt is in its normal or shot position its front
end is situated immediately over the rear end of the trigger and sear, and prevents
the rising of the trigger and sear, and consequently prevents the discharge of
the gun.
This sliding bolt may either be withdrawn by the pressure of the hand in
grasping the gun for firing, the fingers pressing upon a lever which withdraws the
sliding bolt; or the said bolt may be withdrawn by pressing forward a thumb
plate on the upper side of the stock. The said thumb plate is situated on the
top of a nearly vertical lever, the lower end of which is connected to the sliding
bolt.
When the said thumb plate is pressed towards the muzzle of the gun, its lower
end, moving in an opposite direction, withdraws the sliding bolt from over the
trigger and sear and the gun may be discharged.
The cocking of the gun is effected by the rising motion of the breech end of the
barrel in the following manner:-
The first named lever has in its front end a fixed cross pin projecting on both
sides of the lever in a double barrel gun, but projecting on one side only in case of
a single barrel gun. On the breast of the hammer is an arm situated immediately
When the
over and bearing upon the cross pin on the said first named lever.
breech end of the barrel is raised and the lump operates on the first named lever
to bring the safety apparatus into action, the said pin lifts the arm on the breast
of the hammer, and throws the hammer back into its cocked position, in which
O position it is retained by the bent and sear, and the gun is ready for discharge.
Or.the cocking of the gun may be effected by the rising of the lump on the
barrel without the intervention of the first named lever of the safety mechanism.
In this case the breast of the hammer carries on its inner side or face a pin or
projection, the inner end of which is situated immediately over the projecting lower
5 end of the lump. On the raising of the barrel the lump lifts the pin or projection
on the inner side or face of the breast of the hammer, and thereby throws back the
hummer, which is retained in its cocked position by the sear and bent.
My improvements are applicable both to single and double barrelled guns and
pistols of the kind described.
I will now proceed to describe with reference to the accompanying Drawings the
manner in which my Invention is to be performed.

page_text: Figures 1 and 2 represent longitudinal vertical sections of the breech end of a
double barrel drop down gun_containing safety apparatus and cocking mechanism
constructed according to my Invention, the section Figure 1 being taken through
the middle of the body, and the section Figure 2 being taken through one of the
hammers. In Figure 1 the barrels are represented after having been lifted from the
break off, in taking which position they have cocked the hammers and put the safety
apparatus into its acting or safety position, and in Figure 2 the hammers are
represented cocked, and the safety apparatus in action, the sears and triggers being
locked down for preventing the accidental discharge of the gun. Figures 3 and 4
represent side elevations of the gun with the safety apparatus in its withdrawn or
non-acting position, the hammers in Figure 4 being indicated in their discharged
positions; Figure 5 represents a cross section of the gun taken at the face of the
break off; Figure 5A represents a plan of the body, the hand lever for working the
top bolt being removed; and Figure 5B represents the plate carrying the safety
appliances.
Figures 2A, 2B, 6, 7, 8, 9, 10, 11, 12, 13, 14, and 15, represent parts of the gun
separately, as herein after explained.
The same letters indicate the same parts in the several Figures of the Drawings.
I will first describe the safety apparatus of the gun.
I
On the fixed axis a, on which the hammers b, b, turn, is a cam shaped lever c,
shown separately in Figure 6. The front or long arm of the lever c is acted upon
by the lower end d² of the lump d on the barrels when the said barrels are raised
for reloading them, as illustrated in Figure 1, the said long arm of the lever c,
when the safety apparatus is in its withdrawn or non-acting position, resting upon
the said lower end d² of the lump, as indicated in dotted lines in Figure 2. The
rear or heel end of the lever c engages with a second lever f (represented separately
in Figure 7) pressed into the position shown in Figure 2 by a spring e, and behind
the said second lever f is a sliding bolt g working in the fixed case h on the plate
of the gun. The front end of the said bolt g is so shaped that when it is in its
normal or shot position it passes over the rear ends of the sears i and also over
the triggers, and prevents the said sears and triggers from rising to discharge the
gun, as illustrated in Figure 2. In the middle of the front end of the bolt g is an
incline g² (see Figure 1), which is acted upon by the rear rounded end of the
second lever f so as to push back the said bolt, as herein after explained. The
bolt is pressed into its shot position and also withdrawn by means of the nearly
vertical hand lever (shown separately in Figure 8), the bottom end of the said
lever taking into a slot in the rear end of the bolt g. The top end of the lever k
projects from and works in a slot in the tang of the break off, and is furnished
with a thumb plate for working it by hand. A spring acting on the lever k
causes the bolt g, when at liberty to move, to be pressed into the shot position
represented in Figure 2. The hand lever k is moved into the position, Figure 1,
for withdrawing the bolt g from the sears and trigger, and the said hand lever is
held in the said advanced position, and the safety apparatus held out of action by
means of the spring lever catch working in the tang. This lever catch. Z is
represented separately in Figure 9. In its rear arm is a slot 12, the acting end of
which is shaped for engaging with a tooth near the head of the hand lever k,
as seen in Figures 24 and 28. This lever catch is disengaged from the tooth ³
on the hand lever by the action of the top bolt m, when the latter is withdrawn
to unbolt the gun. For this purpose the rear end of the said top bolt m (shown
separately in Figure 10) is inclined at m², the said inclined end m² being situated
under and being pressed upon by the front arm of the spring catch L, as seen in
Figures 1 and 2. When the hand lever k of the safety apparatus is moved towards
the barrels for withdrawing the safety bolt g the slotted arm of the lever catch
falls by the action of its spring, and when the hand lever has fully withdrawn
the safety bolt g the inclined edge of the slot 12 of the spring catch engages under
the tooth of the hand lever and holds it and the safety bolt g out of action, as
illustrated in Figure 24, and the gun is ready for discharge, the parts of the safety

page_text: After the gun
has been discharged the safety bolt g is released by the act of unbolting the gun
and allowed to take its safety or shot position in the following manner:-
apparatus taking the positions represented in Figures 1, 3, and 4.
The parts being in the positions represented in Figures 2, 3, and 4, the hand
lever n of the top bolt m is turned aside, and the said top bolt withdrawn and the
barrels unfastened. The inclined rear end m² of the bolt m in its back motion
travels over the front end of the lever catch 1, depressing the said front end, and
raising its opposite slotted end from the tooth on the hand lever . The said
band lever is thereby released and takes the position represented in Figure 2 by
the action of its spring k³, at the same time forcing the safety bolt g into its shot or
bolting position. The barrels being unfastened, their breech ends rise, causing the
bottom end d² of the lump d to lift the lever c, and the second lever f with which
As the rounded rear
it is connected, in to the positions represented in Figure 1.
end of the lever f rises it acts against the incline g² on the safety bolt g, and
pushes back the said bolt into the position represented in Figure 1. On shutting
down the barrels after the gun has been loaded, the concave face of the lump & is
brought opposite the nose end of the long arm of the lever c, and by the
pressure of the spring e of the second lever f, the two levers c and ƒ are
made to take the positions indicated in dotted lines in Figure 2, the nose end of
As
the said arm of the lever c resting on the lower projecting end d² of the lump.
soon as the rounded end of the second lever f is removed from the incline g² of the
sliding bolt g, the latter is urged forward into its shot or acting position by the hand
lever, which has been released in the manner before described, the several parts
of the safety mechanism now occupying the respective positions shown in Figure 2.
The front end of the safety bolt is thus brought over the sears and triggers, and
the gun is put into a position of safety.
Figure 2 and Figure 2B illustrate the action of the safety lever k and lever
catch drawn to a larger scale.
Figure 2B represents the position which the tooth of the lever k takes during
the raising of the barrels, by an examination of which Figure it will be seen that
the tooth is not raised sufficiently high to engage on the inclined end 13 of the
slot of the lever catch , so that the lever and bolt g are free to return to their
safety position after the barrels are shut down.
When about to fire, the lever k, being pressed back, permits the slotted end of
the lever catch to descend, and the tooth engaging on the incline 13 of the
slotted catch 4, as illustrated in Figure 2A, the said lever k and the sliding bolt g are
locked in their withdrawn positions, as before described.
When the safety apparatus is not required to be used, it may be held out of
action by means of the spring sliding bolt p working on the underside of the body
of the gun. The bolt p and its attachment plate are represented detached from
the gun in Figure 11. The said bolt slides in a groove in the attachment plate, and
a spring p² engaging in a notch in the attachment plate holds the bolt in its
withdrawn position.
The front end of the second lever f of the safety apparatus is provided with a
takes.
P
3 recess q, into which the bolt
When the bolt p is engaged with the lever f
the two levers c, f, are fixed in the positions represented in Figure 1, and the safety
apparatus is held out of action.
Instead of withdrawing the safety bolt g by means of the lever the said bolt
may be withdrawn by the pressure of the hand in grasping the gun for firing, as
O described and illustrated in Figures 12 and 13 of the Specification of Letters
Patent granted to me on the 21st day of October 1880, No. 4291.
I make the extractor with a flat guiding plate 2 instead of rods, as usual, and I
give the lever 8 by which the extractor is operated the shape represented, and cause
the said lever to take a solid bearing against the body when in its withdrawn
5 position, and a long solid bearing on the fore end when in its acting position, as
represented in Figures 1 and 2. The extractor is represented in end elevation in

page_text: Figure 12, and plan in Figure 13 in connection with the barrels, and separately in
Figure 14.
.
I will now describe the cocking mechanism.
On the breast of each of the hammers b is a projection 62, best seen in Figure 5,
and the separate view of one of the hammers in Figure 15. The inner ends of the
projections 62 of the hammers are situated over the projecting lower end 2 of the
lump d, and when the gun has been discharged the said projections 62 of the
haminers rest upon the said end of the lump, as indicated in dotted lines in
Figure 4.
When the breech ends of the barrels are raised the part d² of the lump d
acts against and lifts the projections 62, 62, of the hammers, and throws back the
said hammers into the positions shown in Figures 1 and 2 so as to cock them, the
hammers being retained in their cocked positions by the sears and bents in the
usual way.
Figures 16 and 17 represent in side elevation partly in section, and Figure 18 in
cross section my arrangement for cocking the hammers by means of a fixed cross
pin carried by the lever c. of the safety apparatus before described; Figure 19
represents the lever c and its crossing pin c² detached from the gun. It will be
seen that the cross pin c² projects on both sides of the lever and works in a curved
slot in the sides of the body. The projecting ends of the cross pin c² are situated
under arms 63 on the breasts of the hammers b. When the breech ends of the
barrels are raised and the part d² of the lump operates and lifts the lever c to bring
the safety apparatus into action as before described, the ends of the cross pin c²
lift, the arms 63, 63, on the breasts of the hammers, and cocks the said hammers
as represented in Figure 17. When the hammers have been discharged, as illus-
trated in Figure 16, their arms 63, 63, are brought immediately over and bear upon
the projecting ends of the cross pin c² ready for the said ends of the cross pins to
act upon them to cock the hammers.
Although I have only represented and described my Invention as applied to a
gun having internal hammers, and to which my said Invention is especially
applicable, yet the cocking mechanism and safety apparatus herein before described
and illustrated may also be applied to small arms having external hammers.
Having now described the nature of my Invention, and the manner in which
the same is to be performed, I wish it to be understood that I do not limit myself
to the precise details herein described and illustrated, as the same may be varied
without departing from the nature of my Invention.
But I claim as my Invention of improvements in breech loading small arms of
the kind commonly called drop down guns and pistols,-
First. The construction and combination herein before described and illustrated
in Figures 1, 2, 24, 2B, 3, 4, 5, 54, 5, 6, 7, 8, 9, 10, and 11 of the accompanying
Drawings of the parts of apparatus for preventing the accidental discharge of drop
down guns and pistols, that is to say, the construction of the levers c and f, the
lever c being actuated from the lump on the barrels, and the combination of the
said levers c and f with the sliding safety bolt g and hand lever l, for the purposes
and substantially as described and illustrated; also the construction of the upper part
of the hand lever and the combination with it of the spring lever catch 1, 12, 13, for
fastening the said hand lever and the safety bolt in their withdrawn or nonacting
positions to permit of the discharge of the gun or pistol; also the construction
described of the heel end of the top locking bolt for disengaging the spring lever
catch from the safety bolt hand lever, when the gun or pistol is unbolted for
reloading it, the several parts being constructed, arranged, and operating substan-
tially as described and illustrated.
Secondly. The arrangement or combination of parts described and illustrated
in Figures 1, 2, 3, 4, 5, and 15 of the accompanying Drawings for cocking the
hammers of drop down guns and pistols on the lifting of the breech ends of the
barrels from the break off, that is to say, by means of the projecting part 2 of the
lump on the barrels acting upon shoulders 62 on the breasts of the hammers.

page_text: Thirdly. The arrangement or combination of parts described and illustrated in
Figures 16, 17, 18, and 19 of the accompanying Drawings for cocking the hammers
of drop down guns and pistols on the lifting of the breech ends of the barrels from
the break off, that is to say, by means of a cross pin on the lever c of the safety
apparatus acting against short arms or projections on the breasts of the
hammers.
In witness whereof, I, the said John Field Swinburn, have hereunto set
my hand and seal, this Twenty seventh day of July, in the year of our
Lord One thousand eight hundred and eighty one.