improvements in Single Irigger Guns.
Year: 1895

page_text: Date of Application, 15th Mar., 1895
Complete Specification Left, 16th Dec., 1895-Accepted, 18th Jan., 1896
improvements in Single Irigger Guns.
I, HENRY ALFRED ALEXANDER THORN trading as Charles Lancaster, of
151, New Bond Street, in the County of London, Gunmaker, do hereby declare
the nature of this invention to be as follows:-
This invention relates to improvements in the lock mechanism of single trigger
double barrelled guns.
Hitherto the objection to single trigger guns has arisen from the difficulty of
preventing the second barrel being accidentally discharged on the firing of the
first barrel, which accidental discharge was effected owing to the backward recoil
of the gun freeing the trigger from the pressure of the finger, and the rebound of
the gun pulling the trigger against the finger thereby discharging the second
barrel.
The object of my invention is to provide against this accidental discharge of the
second barrel.
For this purpose I pivot on the trigger plate a lever the front end of which is in
contact with the tumbler the rear end engaging with a switching trigger blade so
that when the gun is cocked the tumbler will actuate the lever so as to bring the
trigger blade under a sear for the first discharge. At the rear of the switching
trigger blade I fix what I term a time stud so arranged that it will prevent the
switching trigger blade passing from the first sear over to the second sear until it
shall have returned to its normal position when it is carried over to the second sear
by a trigger spring thus providing sufficient delay before the switching operation
can take place, to prevent the accidental discharge of the second barrel.
In a modification of the arrangement instead of employing a timing stud as above
described I make use of a timing bolt so arranged that when the first barrel has
been discharged, the switching trigger blade in its movement will operate my timing
bolt and bring it to its position under the sear of the second lock.
Dated the 15th day of March 1895.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.
Improvements in Single Trigger Guns.
I, HENRY ALFRED ALEXANDER THORN, trading as Charles Lancaster, of
151, New Bond Street, in the County of London, Gunmaker, 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 improvements in the lock mechanism of single trigger
double barrelled guns.
The chief objection to the use of single trigger double barrelled guns as
heretofore constructed has been the liability of accidentally discharging the second
barrel on the firing of the first barrel, which accidental discharge is due to the
recoil of the gun momentarily freeing the trigger from the pressure of the finger,

page_text: and the rebound of the gun pushing the trigger against the finger which naturally
follows the trigger to a certain extent during the recoil.
According to my invention I overcome these objections by employing a switching
trigger blade of novel construction arranged in conjunction with what I term a
"time stud" and by the employment of a lever operated by a cam surface on one of
the tumblers and in order that either barrel may be fired at will or one barrel used
continuously, the said lever is mounted upon a slide: all as hereinafter described.
In the accompanying drawing,—
Figure 1 is an elevation of breech mechanism having my improvements applied
thereto, one lock being removed :
Figure 2 is a sectional plan; and,
Figure 3 is a view similar to Figure 2 but shewing the parts in different
positions :
Figure 4 is an elevation of part of the switching blade and time stud:
Figure 5 is a section on the line 5-5, Figure 1; and,
Figure 6 is a similar view to Figure 5 shewing a slight modification :
Figures 7 and 8 are an elevation and plan respectively of the lever operated by
the tumbler; and,
Figures 9, 10 and 11 are respectively a side elevation, a plan and an end elevation
of the slide upon which the said lever is mounted.
a, a indicate the right and left barrels respectively and b, b1 the respective
tumblers for the same, cach of which has arranged in conjunction with it double
sears c,. c.
rear end.
d is my improved switching blade which is pivotally mounted on a stud e on the
trigger which is pivoted at g in a trigger box h, the said trigger being arranged
to engage with either pair of sears c, c in the usual manner and having a broadened
i is my timing stud arranged in combination with the trigger blade, the
said timing stud having a lip or flange ; which projects into the path of the rear end
of the trigger blade and prevents the movement of the same out of engagement with
one set of sears aud into engagement with the other set, except when the said
trigger blade is in its normal position, the rear end of the said trigger blade being
of a height to allow the latter to pass beneath the lip of the time stop in this
position. is a spring which serves to move the said trigger blade from right to
left when in its lowermost position and keeps the trigger blade to the sears.
With this arrangement it will be understood that when the trigger is pulled the
trigger blade will be lifted, for instance to the position indicated by the dotted
lines in Figure 1, so that the side of the blade is adjacent to the side of the lipj of
the time stop thereby preventing the said trigger blade from moving from right to
left. When the gun is fired the pressure of the finger on the trigger will be
relieved thereby allowing the trigger to move downwards a certain extent but as
the finger will involuntarily follow the trigger as the gun recoils this downward
movement of the trigger blade will not be sufficient to bring the top of the rear end
of the blade as low as the underside of the lip ; so that, when on the rebound of the
gun the trigger is again pressed tightly against the finger, the only effect will be
to again raise the trigger blade to the position indicated by the dotted lines.
When after the first barrel has been fired the trigger is fully released, the top of
the rear end of the blade will come as low as the underside of the lip thereby
allowing the trigger lever to move over into engagement with the scars of the left-
hand barrel ready for the next discharge.
In order to provide an additional safeguard against the switching of the blade d
from the right to the left sears in case the trigger blade should drop sufficiently to
accidentally pass beneath the lip j, I provide that the trigger blade shall in its
movement under the lipj be somewhat retarded so as to give time for the finger on
the trigger to follow it up and stop it before completing its movement.
For this
purpose I arch or curve the lipj as shewn in Figure 5 and I provide a similarly
arched or curved lip or projection on the stud i beneath the rear end of the
blade d so that during the first half of the switching movement of the blade the

page_text: under surface of its, rear end rubs against the projection j and during the remainder
of the movement its upper surface rubs against the under side of the lip j. By
this construction it will be seen that directly the pressure of the finger is imparted
to the trigger during the movement of the blade à under the lip; it will cause the
blade to more to the centre of the lip and be. arrested.
Instead of the lips and j being curved as described they may be formed with
double inclines as shewn in Figure 6. It will also be understood that the lip j' can
be dispensed with and the lip formed straight so that the blade d.can pass the time
stop without being obstructed.
m is the lever (shewn clearly in Figures 7 and 8) by means of which the trigger
blade is moved out of engagement with the sears of the left hand tumbler into
engagement with the sears of the right hand tumbler against the pressure of the
spring 1, the said lever being pivoted upon the screw n and having at one end a
finger o which bears against the left hand side of the trigger blade, and at the other
end a cam projection p, which works in conjunction with a cam recess 9 formed on
the tumbler. So long as the tumbler of the right hand barrel is in the cocked
position shewn in Figures 1 and 2, the cam projection p will rest against the flat
surfacer adjacent to the cam recess q, as shewn in the said figures, so that the
finger o retains the trigger blade in its right hand position against the pressure of
the spring 1: when, however, upon the discharge of the right hand barrel the
tumbler moves forward, the cam recess 9 in the tumbler moves opposite to the cam
projection p, whereby the latter, moves into the said cam recess under the action of
the spring as will be readily understood by reference to Figure 3 which shews the
position of the parts after the right hand barrel has been discharged and the trigger
blade has moved over into engagement with the sears of the left hand tumbler.
When the tumbler b is again cocked owing to the opening of the breech in the
usual manner the inclined surface of the cam recess 7, by acting upon the cam
projection p, will again move the lever to the position shewa in Figures 1 and 2
inoving the trigger blade into engagement with the sears of the right hand lock.
s is the slide to which the pivot n of the lever m is attached, as clearly shewn in
Figures 9 to 11, and by means of which the left hand barrel may be discharged
first or used continuously if desired. This slide is capable of moving a distance
sufficient to move the cam projection p from the position shewn in Figure 2 (in
which it bears upon the flat surface r of the tumbler) into the position shewn in
Figure 3 (where it is opposite to the cam recess q) so that whilst the tumbler of
the right hand barrel remains cocked the switching blade may be allowed to move
over into engagement with the sears of the left hand lock to fire the left hand
barrel without firing the right hand barrel first. If it is desired to discharge
the right hand barrel, it is only necessary to move back the slide from the
position shewn in Figure 3 to that shewn in Figures 1 and 2 which is the normal
position.
The slide s is provided with a finger-piece t and spring-blade u, the latter having
a projection thereon designed to engage with either of the two notches w, w0,
Figure 1, corresponding with the two positions of the slide.
Although I have shewn and described my invention as applied to what is known
as a side or detachable lock gun, it is obvious that it is equally applicable to what
is known as a body or box lock gun by simply forming on the lever m a cam
projection p designed to be operated by the back of the tumbler instead of by a
cam recess therein. It will also be obvious that my improvements may be arranged
so that the left hand barrel will be discharged first instead of the right as herein-
before described.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
1. In a single trigger double barrelled gun, the combination with the trigger of
a nivated blul d

page_text: stop, the rear end of the said blade being of such dimensions as to allow it to
pass the time stop when in its normal position and to allow of a certain amount of
movement of the trigger without the blade switching substantially as, and for the
purpose, described.
2. In a single trigger double barrelled gun, the combination with the trigger of
a pivoted blade, a time stop, with or without curved or inclined lips, a lever
-operated by one of the tumblers for moving the said blade in one direction and a
spring for moving it in the reverse direction, substantially as described.
3. In a single trigger double barrelled gun, the combination of a pivoted
switching trigger blade operated in one direction by a lever from one of the
tumblers and in the other direction by a spring and of a slide carrying the said
lever and adapted to move it so as to allow the switching trigger blade to engage
with the sear or sears of either tumbler, substantially as described.
Dated this 16th day of December 1895.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.