Improvements in or relating to Breech Loading Ordnance.
Year: 1892

page_text: Date of Application, 6th Dec., 1892-Accepted, 28th Jan., 1893
COMPLETE SPECIFICATION.
Improvements in or relating to Breech Loading Ordnance.
A communication by ALFONZO MERCER, of Norfolk, in the County of Norfolk,
and State of Virginia, United States of America, Machinist.
I, GEORGE CECIL DYMOND, M. Inst. M.E., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester,
both in the County of Lancaster, and 323, High Holborn, in the County
of Middlesex, Patent Agent, 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 is an improvement in rapid firing guns, being especially designed
for light ordnance, and its object is to provide a simple but efficient and powerful
breech loading cannon, in which the firing of the gun may be automatically effected
by the movement of the breech block in closing, and which can be successively
loaded, discharged, the empty shell thrown off, and a fresh cartridge replaced and
fired with great rapidity without the possibility of the cartridge being exploded
before the breech block is fully home and locked in the barrel.
A subsidiary object of the invention is to provide devices by which the automatic
action of the gun may be prevented and the time of firing thereof be entirely at the
will of the gunner.
The invention therefore consists,
First. In a novel breech block operating mechanism and cartridge holder, placer
and remover:
Second. In novel mechanism whereby a partial revolution of the breech block
after insertion in the gun barrel will both lock the block and simultaneously cause
first the "cocking" and then the releasing of the firing pin, so that the instant the
breech block is absolutely locked in the gun barrel the firing pin is automatically
released and explodes the charge:
•
Third. In novel devices for facilitating the removal of an exploded shell and the
loading of a new shell into the barrel, and ;-
Fourth. In novel devices for controlling the movement of the firing pin so that,
while it will be always automatically "cocked" by the same movement of the
lever which locks the breech block in the barrel, it will not be automatically
released;
And, finally, in certain other novel details of construction and combination of
parts hereinafter described and claimed.
Referring by figures, and letters of reference marked thereon, to the
drawings;
Figure 1 is a detail side elevation of a breech loading cannon or gun, embodying
the invention and partly broken away to show some of the working parts, the breech
block being retracted and in the position it occupies when an exploded cartridge is
to be removed, or a fresh cartridge to be loaded into the gun;
Figure 2 a longitudinal vertical section through the gun with breech block
closed.
Figure 3 is a detail sectional view illustrating the firing pin controlling cam
groove in the breech block carrier, the position of the carrier in this figure being
reversed.
Figure 4 is an end view of the carrier sleeve showing the breech block in section,
and the cam groove.
Figure 5 is a rear end elevation..

page_text: Figure 8 is a detail view of the firing pin scar, and operating devices thereof.
Figure 9 is a view of the breech end of barrel.
The gun barrel A, which may be rifled, smooth bore or otherwise, is provided at
its breech with partial or interrupted screw threads A' adapted to interlock with
similar opposed threads on the breech block hereinafter described.
B is a carrier consisting, as shown, of a longitudinally movable plate sliding in
a slotted support A' formed on the bottom of the gun at the breech thereof or
otherwise rigidly connected to the gun so that the carrier B can slide under the
breech of the gun as indicated in the drawings.
This carrier can be operated by means of a rack, pinion and crank as indicated
in Figure 2, or by other suitable means. On the rear end of the carrier is an
annulus or sleeve C, in which is journalled the tubular shank D' of a rotatable
breech block D which is of a size to fit within and close the breech of the gun, as
shown, and is provided with interrupted screw threads adapted to interlock the
threads of the breech of the barrel when the breech block is inserted therein, as
before set forth.
By moving the carrier of course the breech block can be put in or removed
from the barrel. The shank D¹ of the breech block extends in rear of sleeve C,
and on it is rigidly mounted a collar E which fits close to the end of sleeve C and
in connection with the breech block prevents longitudinal movement of the shank
in relation to the carrier. The collar E is provided with a handle or arm E' by
which the breech block can be rotated.
The firing pin F extends through shank D' and has its forward end reduced to
pass through an opening in block D in position to explode a cartridge, as usual.
A stout helical spring F surrounds the pin within shank D¹ and is confined by a
collar or filling in the outer end thereof.
The front end of the spring impinges against a collar or pin F2 fixed to the firing
pin within the shank, and when the pin is drawn backward or outward the spring
is tensioned. Normally the pressure of the spring on the pin is but slight, and not
sufficient to overcome the counter force of a spring G slipped on the outer end
of pin F and confined between an adjusting nut G2 on the end of pin and the end
of the shank D¹. By this means the point of the firing pin can be so adjusted
and held in such position, normally, that it will not project beyond the face of
the breech block so much as to interfere with the handling of the cartridge. But,
when spring F1 is compressed, its tension is so great that if suddenly released it
will drive the pin forward with such violence as to cause it to explode the fulminate
of the cartridge. This is an efficient and simple rebounding firing pin.
A stud 3 is secured to the firing pin and projects through a slot D³ in shank D',
within sleeve C, and engages a triangular cammed-way in the inner face of said
sleeve, in which the stud travels as the shank is turned. Said way is formed of
three communicating slots C1, C2, C³. Slot C2 is at the front end of sleeve C, and
transversely thereto, so that when the stud is therein the shank and firing pin can
turn without moving the pin longitudinally; slot C³ is horizontal and communicates
with the bottom of slot C2, and, when the stud is therein, the firing pin can
move longitudinally and freely in the shank; the extremities of slots C², C³ are
connected by a cam slot C, which, as the stud travels therethrough, causes the
the pin to move longitudinally and positively within the shank and tension
spring F.
When the shank is in the position shown in Figure 1, the stud F³ stands at the
upper end of slots C1, C2, and spring F consequently is released, then, by giving
the shank a quarter turn, bringing handle E¹ to a horizontal position, the stud F,
turning with the shank and pin, is compelled to traverse slot C' and in so doing
forces the firing pin outward from the cartridge and compresses the spring F¹, and,
just as the quarter rotation of the shank is completed, the stud reaches the lower
end of slot C¹ and enters the horizontal slot C³, the spring F' immediately drives
the firing pin forward in the shank with sufficicut violence to explode a cartridge
in position in front thereof, and the stud, being thus driven through slot C³, enters

page_text: the lower end of slot C2, and, when the handle E¹ is turned back to upright position,
stud F3 traverses slot C2 and stops at the upper end thereof in position to again
enter slot C¹, if the handle is turned down, the rebound spring of the firing pin
causing it to recede sufficiently to ensure the engagement of the stud with
slot C. The rotation of the shank is regulated and limited by a stud D*, attached
thereto and playing in a slot C in the sleeve, as shown.
E is a spring controlled catch attached to handle E' and adapted to engage a
notch C in sleeve C when the handle is turned down, and hold the same in such
position.
A
H, A, are the cartridge rests and extracting devices. Rest h¹ is a metal plate
standing just in front of block D, and having its upper edge concaved to receive
and fit the cap end of the cartridge, this rest is upheld by and connected to a rod h²
which passes and plays through a longitudinal opening in the base of sleeve C and
is provided with a head or nut on its outer end to limit the inward movement of
rest which however can move slightly toward or from the breech block.
spring h³ may be put on rod h² to normally keep rest h¹ away from the breech
block. Rest H is also concaved on its upper edge to receive and support the
cartridge, as shown, but is pivoted to carrier B, as at H', and is normally upheld
by a spring H2, on the hinge, or otherwise attached. The cartridge to be fired is
placed upon the rests, as indicated in Figure 1, and carrier B is then moved
inward; as the end of the cartridge enters the breech of the barrel, the rest H
strikes the barrel and is tipped over thereby, turning down upon the carrier B,
(which is recessed or flanged so as to accommodate the rests) and slides under the
breech of barrel, as indicated in Figure 2. The other end of the cartridge is
upheld by rest until the breech block enters the breech of barrel, which has an
interior groove or channel A³ to accommodate the rest h¹ and rod h³, as shown, so
that, when the breech block is in position and locked, there will be little or no
passage for gas between the breech block and breech of gun, and the breech of
barrel is not weakened by slotting therethrough as would be necessary if rest h¹
was supported directly on carrier B.
When carrier B is drawn back, rest / catches the head of cartridge, and drags
the shell outward (when exploded or not) and, just before the end of shell passes
out of the breech, the rest H coming from under the barrel is raised by its spring
and receives and upholds the shell, as at first it held the cartridge, so that it can
be easily removed by the attendant. In order to facilitate the removal of shells,
the positive throwing off device shown in drawings may be used; consisting of a
flipper plate I pivoted to carrier B intermediate of the rests H, A. and normally
lying flat upon the plate and a rod I¹ pivoted at one end to an upstanding finger
on plate I near the pivot thereof, and extending forward past rest H to the front
of the carrier, where its end is bent down to form a catch I' that plays in a longi-
tudinal slot in support A². When the cartridge is in, the gun flipper I lies under
the breech of the barrel, as indicated in Figure 2; but, when the carrier B is
moved backward and after the shell is entirely withdrawn from the breech and is
upheld by rests H, ', as described, catch I2 is arrested by the shoulder I' at the
rear end of slot and thereby through rod I¹ throws flipper I violently upward
and the flipper striking the shell knocks it from the rests.
The connection between
rod I' and flipper I should be sufficiently loose to let the latter drop partly back
sufficiently to not obstruct the laying of a fresh cartridge on the rests.
It will be desirable in some cases to prevent the gun firing automatically
after loading, and to do this the firing pin must be locked, just after it is
"cocked."
This may be done by the following devices;-
J designates a sear playing through a slot in the end of shank D' and adapted
to engage a bevelled notch f in the firing pin and upheld in engagement with the
pin by a spring J¹.
K is a sliding bolt extending through the slot in the sear and having a wedge or
cam surface which, when the bolt is pulled outward, depresses the sear and

page_text: for operating the same mounted on the carrier whereby the exploded cartridge is
knocked from the holders after it is withdrawn from the barrel, substantially as
described.
6. The combination of the barrel, the slotted support attached thereto, the sliding
carrier moving in said support, the cartridge rests thereon, and the flipper plate I
mounted on said carrier and operating devices therefor, substantially as and for the
purpose described.
7. The combination of the barrel, the sliding carrier B and the folding rest H,
the movable rest h¹ and the flipper I on said carrier, all constructed and arranged
to operate substantially as and for the purpose described.
8. The combination of the carrier, the breech block journalled thereon, the firing
pin in said block, the tension spring therefor, the stud attached to said pin projecting
through a slot in the block and engaging an endless cam way in the carrier, and
the rebound spring on said pin, all substantially as and for the purpose specified.
9. The combination of the carrier, the breech block journalled thereon, the firing
pin in said block, the tension spring therefor, the stud attached to said pin projecting
through a slot in the block and engaging a cam way in the carrier, and the rebound
spring on said pin, and the handle and catch for turning and locking said block,
substantially as and for the purpose specified.
10. The combination of the barrel, the breech block journalled in a carrier
movable toward and from the barrel, the firing pin in said breech block, and the
stud on said pin projecting through a slot in said breech block and engaging a cam
way in the carrier, whereby, when the breech block is partly turned to lock it in
the breech, said firing pin is cocked; with a sear adapted to engage said pin, and
a sliding bolt for operating said sear, substantially as described.
11. The combination of the carrier, the breech block journalled thereon, the
firing pin in said block, the tension spring therefor, the stud attached to said pin
projecting through a slot in the block and engaging a cam way in the carrier, and
the rebound spring on said pin; with the sear for locking said pin, and the
controlling devices therefor, substantially as and for the purpose set forth.
12. The combination of the barrel, the breech block, and the interrupted screw
fastening between said breech block and barrel, and the rest and extractor attached
to said block and adapted to engage a slot in the breech of the barrel below the
breech block, substantially as and for the purpose described.
13. The combination with the firing pin of the sear J, and slidable bolt K having
an inclined shoulder or bevel k adapted to engage and depress said sear when the
bolt is drawn outward, substantially as and for the purpose specified.
14. The combination with the carrier, of the sleeve thereon, the breech block
having a shank journalled in said sleeve, the firing pin journalled in said shank and
projecting therethrough, the spring on said pin within the shank, and the stud
projecting through a slot in said shank and engaging a triangular cam way in the
sleeve, and the handle for turning said shank, and the slot and pin for limiting the
rotation thereof, substantially as described.
15. The combination with the carrier, of the sleeve thereon, the breech block
having a shank journalled in said sleeve, the firing pin journalled in said shank and
projecting therethrough, the spring on said pin within the shank, and the stud
projecting through a slot in said shank and engaging a triangular cam way in the
sleeve, and the handle for turning said shank, and the slot and pin for limiting the
rotation thereof, and the cartridge holding and extracting devices mounted on said
carrier in front of and below said breech block, substantially as and for the purpose
specified.
WM. P. THOMPSON & Co.,
Agents for the Applicant.