Improvements in Breech-loading Small-arms.
Year: 1889

page_text: Date of Application, 30th Mar., 1889
Complete Specification Left, 30th Dec., 1889-Accepted, 1st Mar., 1890
PROVISIONAL SPECIFICATION.
Improvements in Breech-loading Small-arms.
THEODOR BERGMANN, Gaggenau Iron Works, Baden Germany, Director of Iron
Works, do hereby declare the nature of this invention to be as follows:-
The object of this invention is the construction of a simple breech action for fire
arms. The breech bolt is to be of the kind called single action bolts, for the operation
of which a simple reciprocating or straight motion of the hand is sufficient.
The bolt consists of the breech bolt or cylinder proper which carries the locking rib
or ribs, and the bolt head, which is stationary, that is, which does not turn with the
cylinder proper. The bolt head carries the extractor. The two pieces, bolt and head
together form a cylinder of uniform diameter. The bolt proper is provided with a
central hole throughout its length, through which passes the cylindrical shank or
smaller part of the bolt head. This part of the bolt head projects in the roar through
the bolt proper and there carries a lever or knob which is attached thereto by a screw
or pin upon which it may be turned back or forward in a horizontal plane, when the
gun is in horizontal position.
The part of the shank of the bolt head, upon which said operating lever turns, is
flattened and its front edge is bevelled downward.
The rear end of the bolt proper is to the right and left cut away bevelling rearward
so as to form a slanting surface at either side resembling part of a screw thread. The
bolt head being guided in a straight groove and thereby prevented from turning its
shank projecting rearward and carrying the operating lever is naturally in the same
condition, that is being of one piece with the head it cannot turn, but can only follow
a straight reciprocating motion. The locking rib or ribs of the bolt proper are guided
in the breech case as usual in a groove or grooves, which end in a recess or recesses,
into which the rib or ribs turn for locking.
The breech bolt being open, it is for closing it pushed into the breech case by means
of the operating lever.
As long as the locking ribs or ribs move in their longitudinal grooves the entire bolt
must move forward in a straight line. As soon however as the locking rib or ribs
have reached their seat or recess the operating lever pressing by its bevelled edge
upon the inclined bevelled edge on the end of the bolt proper, forces the latter to turn
and enter with its locking rib or ribs into their recess or recesses, thereby locking the
breech. In opening, the handle or operating lever is swung backwards and thereby
acts upon the other opposite bevelled edge of the bolt proper, thereby unlocking the
same by the reversed process.
Dated this 20th day of March 1880
COMPLETE SPECIFICATION.
Improvements in Breech-loading Small-arms.
THEODOR BERGMANN Eisenwerke Gaggenau Gaggenau Germany Director of
Iron Works 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 :-
My invention relates to breech loading fire-arms and has for its object the

page_text: construction of a simple breech action, of the kind called single or straight action
breech bolts.
The improvements consist in the peculiar construction and arrangement of the
working parts of the breech bolt, the small number and solidity of which parts is
intended to insure a reliable and safe easy operation of the breech action. As it is
quite immaterial what kind of striking or firing mechanism and what pattern of
extractor is employed in connection with this improved breech bolt, no reference is
made in the drawings and specification to these parts or devices.
In the annexed drawings a breech action constructed according to my invention is
shewn, of which―
Fig. 1. is a right side view of the breech action or part of a gun with closed breech
bolt.
Fig. 2. is the same view with open breech bolt.
Fig. 3. is a top view of the breech part of a gun with opened breech bolt.
Fig. 4. is also a top view but with closed breech bolt.
Fig. 5. is a left side view of rear part of the breech bolt when closed.
Fig. 6. is the same view with opened breech bolt.
Fig. 7. is a longitudinal vertical section through the breech receiver and breech
bolt.
Fig. 8. is a top view of the breech bolt as removed from the breech receiver.
Fig. 9. is a rear view of the breech bolt.
Fig. 10. is a top view of the rear part of the breech bolt in its locked position and
with its cap or cover removed.
Fig. 11. is a rear view of the same.
Fig. 12. shows in three views the cap or cover as removed from the breech bolt.
Fig. 13. is a cross section through the breech receiver and bolt through line w. ;
in fig. 7.
Fig. 14. is a similar cross section through line z, z, in fig. 7.
Fig. 15 indicates in a similar cross section the possibility of employing four locking
lugs instead of two.
This improved breech bolt consists, without the firing mechanism, which as before
said, is not to be considered, of three principal parts, viz. the breech bolt proper B. the
locking part B and the operating lever C. The breech receiver A has by preference
the usual form. The breech bolt proper B is of cylindrical shape, and is at its rear
provided with a cylindrical shank B of smaller diameter. Upon the shank B² fits
the locking part B₁ which is also cylindrical and of the same diameter as part B, and
which carries upon its circumference near its forward end, where it joins part B, the
locking ribs bb. diametrically arranged. Shank B2 is longer than part B and
projects from the rear thereof as shewn in fig. 10. This projecting end of shank B is
at one place flattened or cut down for the reception of the operating lever which is
movably attached thereto by means of a screw c. This arrangement permits of a
horizontal swivelling movement of the operating lever upon shank B². The rear edge
of locking piece B₁ is at the right and left cut away slantingly so as to form at either
side an inclined surface d and respectively as shown in fig. 8. Lever when
moved forward will operate upon the right inclined surface d' and bolt B and with it
shank B being prevented from turning will cause locking part B¹ to make part of a
revolution amounting to about 45 degrees, whereby the locking of the bolt is effected
in the manner to be described below. When drawn back operating lever acts upon
the opposite inclined plane or surface d' of part B and causes it to make part of a
revolution in the opposite direction, whereby the unlocking of the bolt is effected. In
order to facilitate these movements and to ensure an easy working, the forward edge
of operating lever C, which acts upon the inclined surfaces d, d' is also slanting or
chamfered off as shown in Fig. 7. The breech receiver is in its rear part, provided
with two diametrically arranged longitudinal slots or grooves a, a, which correspond
in size and position to the locking lugs b, b, of part B¹. Grooves ay a, each terminate

page_text: forwards into a transverse groove a¹, a', to the left and right respectively, (fig. 14) for
the reception of the locking lugs b, b, when piece B¹ is turned. The cylinder or bolt.
proper B is on its outside provided with a groove e which however does not extend
over its entire length, but terminates a little short of its forward end. In the rear,
groove e is continued into locking piece B₁ where it terminates in a short transverse
groove as shewn in fig. 6. A suitable stud or pin fixed into the breech receiver fits.
into said groove e, and thus serves as a guide to bolt B and prevents it from turning
so that only a rectilinear movement of piece B is permitted. Groove e terminating
short of the end of piece B, prevents the bolt from being drawn out entirely from the
breech receiver, while the transverse groove in locking piece B permits the turning
of that piece, when the bolt is being locked. As this way of guiding breech bolts is
well known, the way of applying this device is immaterial here, and only by way of
example the guiding pin for groove e is here supposed to be attached to a small
hinged lever held in position by a spring E. This arrangement would permit by
pressing upon lever E to withdraw the guide pin and thus to remove the breech bolt.
entirely from the breech receiver. The breech bolt is operated as follows. Being
open in the positions shown in fig. 2, 3 and 6 the bolt is pushed into the breech.
receiver by its operating lever C. The lower locking lug being guided at first in a
groove in the breech tail (fig. 4) and when it enters the breech receiver in its
proper groove a piece B₁ is prevented from turning and forced to move in a
rectilinear direction until the bolt is completely closed. Lugs b, b, coming now in
juxtaposition to the transverse grooves or recesses a³, a', terminating the longitudinal
grooves a, a, a continued forward pressure against the operating lever C will cause
the latter to swing forward upon its axis and in doing so to act upon the inclined
surface d of locking piece B¹, which thereby receives about one quarter turn to the
right whereby lugs b, b, enter recesses a, a, and the bolt is locked. In opening the
breech bolt, the reverse takes place. Operating lever being pulled, swings back
and acting upon incline d' causes part B¹ to make one fourth of a revolution to the
left, whereby lugs b, b, are turned out of recesses a' a' into grooves a, a, whereupon
the bolt may be drawn back. In order to cover and protect the rear part of the bolt
where the operating lever is joined to it, and for giving an even and finished
appearance to the whole, a cap D is provided which is attached to shank B² by means
of a ping as shown or in any other suitable manner. Cap D is at its lower part
provided with a rigid rib D' which is guided in groove of the breech tail and serves
to give additional steadiness to the reciprocating of the breech bolt.
Locking lugs b, b, may be replaced by a locking rib as employed in the Mauser,
Berdan and other rifles, or instead of two lugs, three may be provided, or even four,
as indicated in fig. 15. As a matter of course the breech receiver must be provided with
the corresponding number and kind of recesses to receive the locking lugs or ribs of
the bolt. The locking lugs and their recesses may also be provided with corre-
sponding screw threads or the lugs and recesses themselves may be formed or
arranged to act like screw and nut so as to serve for a better tightening and loosening
of the bolt. The latter especially would be valuable for facilitating the extraction of
the cartridges.
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 breech loading fire-arms a breech bolt having a rectilinear reciprocating
motion and consisting of the cylinder or bolt B, and of the locking part B', which
turns upon a shank B' rigidly attached to, or in one piece with bolt B part B¹
provided with one or more locking ribs or lugs b, b, and shank B2 provided with
operating lever C, swivelling in a horizontal direction and acting alternately upon
inclined surfaces d and d of part B' substantially for the purpose and as herein
described and shown.

page_text: (2) In breech loading fire-arms with a breech bolt of the kind herein described a
cap D attached to shank B' of bolt B and provided with a guide rib D₁ running in a
groove fin the breech tail, substantially for the purpose, and as herein described and.
shown.
Dated this 30th day of Decembar 1880
E. EATON,
Agent for Applicant.