Improvements in Breech-loading Fire Arms
Year: 1898

page_text: Date of Application, 25th Oct., 1898-Accepted, 1st July, 1899
Improvements in Breech-loading Fire Arms,
I, SYDNEY PITT, of Sutton, in the County of Surrey, Gentleman, do hereby
declare the nature of this invention (which has been communicated to me from
abroad by Colt's Patent Fire Arms Manufacturing Company, of Hartford,
Connecticut, United States of America) 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 generally to the class of automatic breech loading fire
arms and more especially to fire arms of this description in which the several
operations, such as the opening of the breech after firing a shot, the ejection of
the empty cartridge shell, the cocking of the hammer, the presentation and intro-
duction of a fresh cartridge into the chamber of the barrel, and the closing of
the breech, are automatically effected by the pressure in the barrel of the gases
generated by the explosion of the cartridge.
The invention comprises further improvements in fire arms of the class described
in the Patent No. 9871 dated the 20th day of April 1897, said patent containing
some of the features of the complete fire arm which I have illustrated and described
herein for the purpose of enabling the present invention to be understood. Such
features as are common to the two constructions will be referred to herein so
far as may be necessary to enable the present invention to be understood, but the
lescription which follows will relate particularly to the novel features of this case.
The main object which has been had in view has been the production of a fire
arm of the class referred to which should be simple and inexpensive in construc-
tion, not liable to get out of order, and reliable and safe in operation under all
conditions of use. I have hereinafter shown and described the present improve-
ments as adapted to a gas operated, magazine pistol, but I have chosen this
particular kind of fire arm merely as a convenient illustration of an embodiment
of the invention and do not intend to restrict the invention to an application
thereof to a magazine pistol nor to any particular kind of fire arm', nor do I
Fintend to restrict the invention to the use of the several features of improvement
together in a common structure.
F
In the accompanying drawings, in which I have illustrated an embodiment of
the invention.
Figure 1 is a left hand side elevation of the pistol with the breech closed.
Figures 2 and 3 are respectively rear and front end views of the same.
Figure 4 is a longitudinal section on a vertical plane, with the breech closed.
Figure 5 is a longitudinal section on a vertical plane, with the breech open.
Figures 6, 7, 8, and 44 are detail views of parts to be referred to.
Figure 1 is a horizontal section on the plane indicated by the line a-b of
Figure 1.
Figure 1B is a horizontal section on the plane indicated by the c-d of Figure 1.
The pistol represented in the accompanying drawings comprises a frame a,
a barrel b fixed in the frame and a sliding breech piece C. The upper portion
of the frame a forms the receiver and has a seat and suitable guides for the
reciprocating breech piece, and below the receiver is the grip or handle a¹ which

page_text: '
is preferably made integral with the frame, but obviously may be formed separately
and attached thereto in any suitable manuer. Within the grip and extending
through the same upward into the receiver is arranged a seat or chamber for the
reception of the cartridge magazine d. The latter is substantially of ordinary
form and construction, and may consist of a sheet metal tube in which the cart-
ridges are laid one upon another, resting upon a spring follower, by which they
are pushed upward into the receiver. It is conveniently retained in place within
the grip by a spring actuated latch . Its upper end is open to permit the
escape of the cartridges, the side walls at the rear of the opening being turned in
to engage the rim or flange of the top-most cartridge and prevent the escape of
the same from the holder except when it is pushed forward as hereinafter
described.
to
The barrel b is secured to the receiver in any usual or suitable manner and
extends forwardly from the same to the desired length. The upper portion of
the frame is provided interiorly with longitudinal ribs and grooves a³ a (Figure 2)
engage corresponding ribs and grooves of the breech piece c, or of that
portion of it, which may be more properly designated as the breech bolt, the
said breech bolt or breech piece being thereby held to the frame and guided
thereon in its reciprocation. On the top of the breech bolt is a strong longi-
tudinal rib. to which the portion of the breech piece is secured firmly by
means of screws which pass transversely through said portion and the rib,
the central portion of the rib being increased in width and the slot in the slide c
being correspondingly shaped to secure a stronger attachment, if desired. The
part slides upon the frame and extends forwardly so that when the breech bolt
is in closed position the front end of said part or slide stands over the muzzle
of the barrel. In order that the slide may be accurately guided in its movement
its forward portion is extended downward, preferably in the form of a sleeve
which embraces the forward portion of the barrel, an open space being left
between the rear end of said sleeve c and the part of the frame a supporting the
barrel, to allow for the longitudinal movement of the sleeve with the slide and
breech bolt. The slide is bored out to form a longitudinal chamber, from
the breech bolt forward, to receive the reaction spring e, and at the front this
chamber is closed by a screw plug 8.
The reaction spring e is a strong spiral spring, the rear end of which stands
against the shoulder a² of the frame, which at the breech end of the barrel projects
upward into the chamber of the slide A plug e is secured to the forward
end of the spring e and is fitted to slide freely in the chamber of the slide.
The forward part of the top ribof the breech bolt is divided by a vertical
cut, forming a seat for the lever 1, which is pivotally attached to the rib ², and
depends through a vertical opening in the body of the breech bolt c¹. To the
central part of the lever is attached the connecting rod 1, which extends forward
from the lever through a cut in the part a² of the frame and through the spring e
to the plug e, which is firmly attached to the forward end of the rod 1, thereby
maintaining the reaction spring e in a state of compression. When the breech
bolt is moved to the rear, either by hand or by the powder gases, the breech is
opened, and, through the described connection, the reaction spring e is further
compressed, so that, on the release of the breech bolt, the spring e returns the slide
and the breech bolt to their forward position and thereby closes the breech. The
rear end of the sleeve and the face of that portion of the frame a which supports
the barrel limit the rearward movement of the sliding breech piece or slide and
breech bolt. The space between the sleeve and the frame, when the former is in
its forward position, is covered by a shield or cover a³, which I prefer to make
integral with the frame and which extends forward from the frame to the sleeve
without interfering with the movements of the latter. As described heretofore,
cartridges are pressed upward from the holder or magazine d but are held from
escaping therefrom. Nevertheless the rim or flange of the topmost cartridge
rises above the holder as soon as the breech bolt c¹ has passed to the rear of the
holder, so that in the forward or closing movement of the breech piece the face of

page_text: the breech bolt engages the topmost cartridge, and pushes it directly from the
holder into the chamber of the barrel. When the cartridge is exploded the
breech bolt is driven backward by the powder gases and in its movement it effects
the extraction of the empty shell from the chamber of the barrel and its ejection
from the receiver. For this purpose an extractor f of usual construction is
arranged in the side of the breech bolt c, to engage the head or flange of the
cartridge during the closing movement and to extract the shell from the chamber
of the barrel during the opening movement. As the shell is drawn rearwardly
by the extractor, which engages the flange on the right hand side, the left hand
edge of the flange strikes a projection on the left hand side of the receiver so that
the shell is ejected through the opening as formed in the right hand side of the
frame for that purpose.
•
The improved firing mechanism varies in part from that described in the said
patent and will be briefly explained herein so that the operation of the fire-arm
may be fully and clearly understood. The breech bolt c is chambered as usually,
forming a seat for the striker k, the forward part of which forms the firing pin,
and the level passing, as described above, through an opening in the body of
the breech bolt, extends into a vertical slot in the hammer k, and under the
action of the springe and the rod the lever forces the hammer to its forward
position, and the forward movement of the rod is transmitted to the breech
bolt c¹ by the lever at its pivot and also at its point bearing against the hammer.
Below the receiver and the breech bolt the sear 9 is pivotted in the frame, in
rear of the grip, and is provided with the usual sear spring g', and the breech
bolt is slotted and the hammer k is provided with the usual cock notch k¹. In
front of the grip the trigger h is pivoted in the frame and from the trigger a
connecting piece h¹ extends to the sear and serves to transmit the rearward move-
ment of the trigger to the sear, without interfering with the cartridge magazine.
The spring returns connecting piece h¹ and the trigger h to the forward position
when the latter has been released. When the breech bolt is moved to the rear,
in opening the breech; the hammer k moves with it and the notch k¹ passes to
the rear of the sear nose (Figure 5); on the release of the breech bolt the extension
of the spring e transmitted through the rod to the lever 1 causes the latter to
return the breech bolt forward, but when the notch k¹ arrives above the sear nose
the latter enters the notch and retains the hammer at full cock, as shown in
Figure 4 and in Figure 4 in dotted lines. During the remainder of the closing
movement the extension of the spring e is transmitted to the breech piece through
the lever at its pivot only, and when the breech bolt arrives fully forward the
lever assumes the position shown in dotted lines in Figure 4, inclining rearward
from its pivot and its point resting against the forward portion of the hammer.
If now the trigger is pulled rearward, the sear nose is moved down out of the
path of the hammer and the latter is thrown forward by the lever under the
force of the spring e. In this manner the spring e not only serves to close the
breech, but also causes the hammer to strike the firing blow upon the cartridge,
and thus makes the addition of the usual main spring for this purpose unnecessary.
For perfect safety in handling and carrying this pistol, even when loaded and
with the hammer at full cock, I have provided a strong horizontal bolt i which
passes transversely through the frame below the breech bolt and between the sear
and the hammer (Figures 1, 1B, 4, 4, 5 and 6). On the outside of the frame
the safety bolt i has a handle by which it may be turned through an angle of
about 90°, (Figures 1 and 1B), and segments of the bolt i are cut away, so that
if it is turned to the position shown in Figures 4 and 5, the breech bolt may be
moved rearward, and the sear may be moved to release the hammer.. In the bottom
of the breech bolt I provide a transverse recess 22 which stands above the safety
bolt when the breech is closed (Figures 4 and 4^) and into which a portion of the
bolt enters if it is turned from the position shown in Figure 4 to that shown
in Figure 4, thus securely locking the breech bolt in its forward or closed position.
In this position the central part of the safety bolt i bears against à shoulder

page_text: formed on the sear 9 above its pivot, (Figure 44), and positively locks the sear,
and prevents it from releasing the hammer, if the latter is in the full cocked
position. As the hammer cannot be seen when the breech is closed, I provide a
projecting point on the lever / in front of its pivot, this point can be seen in
the lever's seat from the outside when the hammer is forward but disappear when
the latter is cocked, thus serving as an index to show the position of the hammer,
(Figure 4).
a
In Figure 6 a convenient method of yieldingly retaining the safety bolt i in
either of its positions is shown. For this purpose I arrange in the side of the frame
à hole radial to the bolti and in it a short piston, spiral spring and screw plug
closing the hole, the piston has a conical point and two correspondingly shaped
recesses in the safety bolt i serve to yieldingly hold the latter in its two positions.
In Figures 1 and 1A, I have shown a novel, simple and efficient way of remove-
ably attaching the cheek-pieces upon the pistol grip, when the interior of the
latter is utilized as a magazine seat. On the inner surface of each cheek-piece m,
I form a part m' which slightly projects into the opening in each side of the grip,
thus preventing the cheek-pieces from moving in any direction but outward. Upon
the part m each cheek-piece has a plate m³ of oblong shape and attached to the
cheek-piece so that it may be readily turned from the outside, as by a stud and a
nut m provided on the outside with a slot. Within each side of the grip a
shallow partly circular recess forms a seat for the oblong plate, which in the
position shown in Figures 14 and 4 securely locks the cheek-piece in place, while
to remove it, the nut m³ and with it the plate m² is turned through an augle of
90° whereby plate and cheek-piece are released.
For the better lateral support of the breech bolt in its closed position, a stud be
projects from the barrel band enters a corresponding recess in the face of the
breech bolt c¹ when the latter is in its forward position. The stud 6s also assists
in the proper introduction of each cartridge into the barrel, as it guides the bullet
end of the cartridge.
From the foregoing description it will be understood that the breech bolt is
not positively locked in the closed position but is yieldingly held in such position
by the reaction spring e. On firing, the breech bolt yields to the pressure of the
powder gases in the barrel, which pressure forces the cartridge shell and breech.
bolt rearward. By this construction I am enabled to make the frame and the
barrel of such lightness that the breech bolt and the breech slide, together con-
stituting the breech piece, as it has been denominated herein, may be of great
strength and weight, and as the inertia of these parts has to be overcome in open-
ing the breech, their weight serves as a safeguard by retarding the opening of the
breech until the bullet has passed from the muzzle; the momentum of the heavy
breech bolt and slide completes the rearward movement, after the pressure in
the barrel has been relieved, ensures the extraction and ejection of the cartridge
shell, and stores energy in the reaction spring for the closing movement, without
exposing this spring to the shock which would be occasioned if the breech piece
was of lighter weight. The strength of the moveable parts and the fact that the
front of the frame serves as a stop to arrest their rearward movement, ensures
the safety of the arm even if the reaction spring should break.
The operation of the improved fire-arm will be readily understood from the
foregoing. A filled cartridge holder is inserted in the grip and the breech slide
is drawn rearward once by hand. This opens the breech, cocks the hammer,
presents a cartridge in front of the breech bolt, and compresses the reaction
spring. When the breech slide or breech piece is released, the reaction spring
returns it to the forward position and transfers the topmost cartridge from the
holder to the barrel. If now the trigger is pulled and a shot fired the breech
is automatically opened, the hammer is again cocked, the empty shell is extracted
and ejected, and a new cartridge is presented, energy being at the same time
stored in the reaction spring to effect the forward movement of the breech piece.
These operations are repeated so long as cartridges are supplied.

page_text: It will be understood that the features of improvement which I have described
herein are not necessarily combined in the same structure with the other features
of the fire-arm which, for purposes of explanation, I have shown and described
herein, nor are they necessarily employed in a fire-arm of the particular character
of that shown. Obviously also various changes in form and arrangement of parts
may be made within the scope of my invention.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:-
:-
1. In a fire-arm the combination of a barrel, a sliding breech bolt, a hammer,
a lever pivotted to the breech bolt and also engaging said hammer, a spring
acting upon an intermediate point in the length of the lever to move it forward
and a sear for retaining the hammer when it has been carried back by the breech
bolt whereby the one spring serves to draw forward and close the breech bolt and
afterwards to throw forward the hammer when the sear is released.
2. In a fire-arm, the combination with a frame and a barrel carried by said
frame, of a sliding breech bolt, a forward extension attached to said breech bolt
and extending alongside the frame and barrel, and chambered longitudinally, a
shoulder on said frame projecting into the chamber of said extension, a reaction
spring disposed within said extension, having its rear end supported by said
shoulder on the frame and having its forward end fitted to freely slide in said
extension, and a connecting rod having its forward end secured to the forward
end of said reaction spring, and passing through said reaction spring and through
said shoulder on the frame, and having its rear end pivotally connected with said
breech bolt.
3. In a fire-arm, the combination with a frame and a barrel carried by said
frame, of a sliding breech bolt, a forward extension or arm attached to said breech
bolt and extending forward alongside of the frame and the barrel, and bored out
or chambered longitudinally, a reaction spring disposed within said extension or
arm and having its rear end supported by said frame, a hammer arranged within
said breech bolt, a lever pivotted in said breech bolt and extending into a recess
in said hammer, and a rod having its rear end connected to said lever and having
its forward end connected to the forward end of said reaction spring.
4. In a fire-arm, the combination with a frame having a grip or handle to
receive the magazine, and a barrel, of a sliding breech bolt, a forward extension
attached to said breech bolt and extending alongside of the frame and barrel, and
chambered longitudinally, said extension having a sleeve surrounding the barrel,
a shoulder on said frame projecting into the chamber of said extension, a reaction
spring disposed within said extension and having its rear end supported by said
shoulder on the frame and having its forward end fitted, to freely slide in said
extension, a connecting rod having its forward end secured to the forward end
of said reaction spring, and passing through said reaction spring and-through
said shoulder on the frame and having its rear end pivotally connected with said
breech bolt, and cartridge-exploding, shell-extracting and shell-ejecting devices
carried with said breech bolt.
5. In a fire-arm, the combination with a frame having a grip or handle to
receive a magazine, and a barrel, of a sliding-breech bolt, a forward extension
or arm attached to said breech bolt and extending forward alongside the frame
and barrel, said extension or arm being bored out or chambered longitudinally
and having a sleeve surrounding the barrel, a reaction spring disposed within
said extension or arm and having its rear end supported by said frame, a hammer
carried by said breech bolt, a lever pivotted in said breech bolt and connected
with said hammer, a connecting piece between said lever and the forward end of
said reaction spring, and shell-extracting and shell-ejecting devices carried with
said breech bolt.
6. In a fire-arm, the combination with a frame, a barrel carried by said frame,

page_text: a sliding breech bolt and a hammer arranged within said breech bolt, of a lever
pivotted in said breech bolt and engaging said hammer, and a reaction spring
supported at one end by said frame, and having its other end connected with
said lever.
7. Fire-arms constructed substantially as herein before described and illustrated
in the drawings annexed.
8. The combination with the grip of a pistol frame, of a cheek-piece having
a projection' to enter the opening in the side of the grip, an oblong plate movably
attached to the cheek-piece, a recess within the grip for the reception of the ends
of said oblong plate, and means for turning said plate to engage said recess, and
to disengage it therefrom.
11
1
1000
SYDNEY PITT.