Improvements in and in connection with Automatic Fire Arms.
Year: 1899

page_text: Date of Application, 17th Aug., 1899-Accepted, 30th Dec.,
1899
COMPLETE SPECIFICATION.
Improvements in and in connection with Automatic Fire Arms.
I, FERDINAND RITTER VON MANNLICHER, of I Getreidemarkt No. 10, Vienna,
Austria, Engineer, 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:―
The improvements that form the subject of this invention relate to automatic
small arms having a fixed barrel and having a breech bolt closure which latter
is operated by powder gases from the barrel, the said gases acting through a
passage in the barrel, upon a piston that moves in a gas cylinder parallel to the
axis of the narrel and breech closure.
The improvement in the actuation of the breech bolt consists in that the gas
piston which is driven back by the gas for a short distance, has only to effect the
unlocking of the breech bolt, and imparts to the breech bolt after or during the
unlocking operation a backward push or impulse in the direction of the longi-
tudinal axis, but does not accompany the breech bolt during the whole of its
backward movement. In fact the gas piston, after completing its short travel
is again shot forwards independently by a spring into its initial position, whilst
the breech bolt by reason of the momentum imparted by the short but quite
sufficient impulse it has received, completes its return travel and is then again
driven forward by its own helical spring, so as to effect the closing, and locking
action. The object of this arrangement is to enable the operation to be effected
by means of a very short and therefore strong and light gas cylinder and gas
piston, and also to render the remaining greater part of the movement of the
breech bolt independent of the gas apparatus, so that by closing the gas outlet
aperture in the barrel, the breech mechanism can be operated quite independently
of the gas apparatus, as in an ordinary repeating gun.
This construction removes all disadvantages which were inherent in the exist-
ing constructions of this kind, and it allows of producing a simple gun certain
in action and compact in external appearance, which will comply as far as possible
with practical requirements.
This construction is applicable to straight-pull breech closures, as well as to
breech closures with turning movement, and the locking of the breech mechanism
on firing can be of any suitable kind.
The accompanying drawings illustrate an automatic gun constructed in accord-
ance with my invention. In these drawings;-Fig. 1 is a vertical section of
the same with closed breech and with the hammer shot forwards.
Fig. 2 is a similar section with open breech and cocked hammer.
Fig. 2 is a cross section on the line A-B of Fig. 1.
Fig. 2b is a cross section on the line C-D of Fig. 1.
Fig. 2 is a cross section on the line E-F of Fig. 2, looking from the front
end.
Fig. 2 is a cross section on the line G-H of Fig. 2, looking from the rear

page_text: Fig. 5 is a right hand, and Fig. 6 a left hand external elevation of the rear
part of the gun.
Fig. 7 is a right hand complete view of the gun, and Fig. 8 is a plan of the
same.
Figs. 9 and 10 shew a loading strip for the magazines of guns of this kind.
Figs. 11 and 12 are respectively an underside view and a side elevation of
part of a gun in accordance with this invention, with modified breech closure.
The breech closure a consists of a breech bolt with turning motion and is
guided in the casing b. The latter is extended backward in the form of a
easing or sleeve to such an extent that the breech bolt, even when in its rear end
position, will not project beyond the same, and will therefore always be covered
thereby so that in firing, neither the hand nor the face of the marksman is
endangered by the breech bolt moving back at a great speed. Before I proceed
to describe the breech bolt more in detail, I shall describe the gas apparatus and
its action upon the breech mechanism. The barrel c is provided at e (Figs. 1
and 2) with a small channel through which the powder gases can pass into the
gas cylinder d when the projectile has moved beyond the said channel. The gas
cylinder is fixed parallel to the barrel and below the same by means of a screw
or in any other suitable manner. In the gas cylinder d there moves the gas
piston e which is made in one piece with the cranked slide-arm e¹ (Fig. 4) that
extends rearwards and laterally. This arm e' is guided in a slot in the casing b,
and extends with a nose or pin ell into the bore of the said casing. The breech
bolt is provided at the place, corresponding to the pin el, with an incised
recess of the form shewn in Fig. 3, when the breech is locked and the gas
piston e is in its forward position, the pin ell of the latter lies against the front
part of the helical face of the recess a¹. In firing, the pin el which moves
back with the gas piston, slides along the face a", and thus compels the breech
bolt to rotate with an opening movement to the left until its stud 1 (of which
there may be two or more) has moved out of the recess 6 Fig. 5, formed in the
casing or in the prolonged end of the barrel. For the purpose of producing the
rearward motion of the bolt a, which is to be continued in an axial direction, it
is generally sufficient to give the breech bolt the slight opening movement (which
is usual in breech bolt closing mechanisms) at the end of the turning motion
that effects the unlocking; but for the purpose of insuring the rearward movement
of the cylinder, there may be given to the latter by means of the pin c¹¹ a
rectilinear rearwardly acting impulse for which purpose this pin ell after arriving
at the end all of the recess a¹ continues its rearward movement for a further short
distance and then stops, owing to the rearward motion of the gas piston e being
arrested by a suitable stop, whereupon it is at once pushed forward by a spring elli
The bolt a now continues its rearward movement independently, by reason of the
impulse it has obtained, effecting the cocking of the hammer f which remains
cocked until the next shot is fired, by reason of the construction which is
usual in automatic fire arms of this kind. At the same time the closing spring
is compressed until the bolt has completed its rearward motion which is limited
in any suitable desired manner.
In the rearward movement of the bolt, the cartridge case is carried along with
it by means of a cartridge extractor arranged in the usual manner, and it is
ejected by striking against an ejector nose also in the usual manner. The bolt a
can now begin its forward movement by the pressure of its closing spring g,
and it takes a cartridge from the magazine and inserts it in the barrel.
The magazine is shewn in the drawing as a revolving drum magazine capable
of being loaded by means of a push-out packet. At the end of its forward
movement the bolt a must again be turned to the right hand in order to become
locked. This is effected by the closing spring which is fixed at one end in
the breech bolt a, and at its other end to the end of the breech casing in such a
manner that it in being compressed is also subjected to torsion, so that it has a
constant tendency to rotate the bolt a to the right hand into its locked position.

page_text: The channel in the barrel leading to the gas cylinder may be closed by means
of a screw to allow the gun to be used as a non-automatic repeating arm. In
this application the closing spring g may be retained or it may be removed. If,
in using the arm automatically the closing spring should break or become in-
operative, the breech bolt must be closed by hand, but the gun will also remain
capable of being used as a repeating arm in such case. The other details of
construction which do not form the subject of the present patent can be seen
from the drawing and it need only be noted that instead of the revolving drum
magazine, any other kind of magazine might be employed, but that the former
is to be recommended because with a capacity of 5-6 cartridges it corresponds
best with the shape of the stock of the gun. Also a magazine of this kind can be
unloaded in a very simple manner.
The construction shewn in Figs. 11 and 12 illustrates the use of the present
invention in a gun with a straight pull, in which the locking of the breech
bolt a is effected by means of a locking catch R that turns on a transverse axis,
and is acted upon by a spring R' and which catch when the breech is closed
engages behind a stepped portion or shoulder R2 on the breech bolt a and thus
locks the latter. If in firing a shot, gas should enter the gas cylinder d, the gas
piston e will be shot back as before, and an inclined surface K on the rod e¹ of
the same presses upon and slides over the inclined forward end K¹ of the catch R,
and thus presses the latter down so as to bring it out of the engagement with the
breech bolt a, thus unlocking the latter, whereupon the stud K on the bar e¹
strikes against the shoulder R2 on the breech bolt and imparts to the latter in
the axial direction the necessary impulse for opening the same. Then the breech
bolt shoots back as before by reason of the momentum it has received in this
manner, whilst the gas piston is moved back by its spring into its initial position.
The breech bolt is then again shot forward by its spring in order to close the
breech, and the catch R is caused by the action of its spring R¹ to bear against
the rear end of the breech bolt so as to lock the latter. It is to be observed that
the two arrangements herein before described are to be considered merely as
examples of the adaptation of the present invention to guns having various arrange-
ments of breech mechanisms and that the breech mechanisms as such do not
form part of the present invention.
The essential feature of the present invention consists in the fact that the
gas piston in moving back effects only the unlocking of the breech closure and
imparts to the breech bolt an impulse of such strength as to cause this breech
cylinder by reason of the momentum it has thus acquired, to complete the opening
movement, so that the stroke of the gas piston is very much smaller than the
stroke of the breech bolt. With respect to the loading strip, it is to be noted
that in the arrangement selected for illustration in Figs. 9 and 10, the spring
lips, which keep back the topmost and lowermost cartridges are stamped out
of the back of the loading strip in such a manner that connecting pieces
are left at top and bottom which can be further strengthened by bending up
the edges of the sheet metal at 61 62. Similarly, the two spring lips as also
the edges of the loading strip, may be stiffened by means of longitudinal
ribs y¹ y² y
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1. In an automatic fire arm in which the powder gases issuing through a hole
from the gun barrel, operate the breech bolt a, by means of a gas cylinder d,
and a piston e moving in the same, the arrangement whereby the stroke of the
gas piston e is made such that it is capable of effecting the unlocking of the
breech bolt and of then imparting to the latter a push or impulse in the axial
direction of such strength as to enable the bolt to complete the opening movement
by means of the momentum it has thus acquired, whilst the closing movement

page_text: of 'the bolt and the return movement of the gas piston are effected independently
of each other by means of separate springs g and el whereby the stroke of the
gas piston can be made very much smaller than the stroke of the breech cylinder,
substantially as described.
2. For loading gun magazines, a loading strip made in one piece with inwardly
flexible tongues, 1, at the outer ends, and with turned up end strips b1, b2,
the said loading strip being stiffened by means of longitudinal ribs y¹ y² y³ sub-
stantially as described.