Improvements in Trigger Mechanisms for Breech Loading Fire Arms.
Year: 1891

page_text: COMPLETE SPECIFICATION.
Improvements in Trigger Mechanisms for Breech Loading Fire Arms.
I, FERDINAND MANNLICHER, of I Getreidemarkt 10, Vienna, in the Empire of
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 object of my invention is the construction of an improved trigger-mechanism
for fire-arms with sliding breech bolt. This improved mechanism is intended to
offer an absolute security against the accidental firing of the shot before the bolt
has been completely locked. In combination with the trigger an ejector and a
stop for the bolt are arranged in such manner that, when the bolt is opened, the
said ejector rises to form an abutment for the receding cartridge or shell which is
thereby ejected, while the said stop is formed by a projection of the trigger
reaching through the tail piece of the gun, so as to limit the rearward movement
of the bolt and to prevent it from being entirely pulled out of the breech
receiver.
I will proceed to describe my said invention with reference to the accompanying
drawings in which :-
Figure 1 is a longitudinal vertical section through the lock of a sliding breech
bolt fire-arm with the bolt opened.
Figure 1 is a cross section through the bolt and tail piece on line x-y of
Figure 1.
Figure 2 is the same section as shown in Figure 1, but with the bolt in closed
and cocked position.
Figure 3 is the same section as in Figure 2, showing the position of the bolt after
firing.
Figure 4 shows in side, top, bottom, front and rear views the main or centre part
of the trigger mechanism detached:
Figure 5 shows in the same five views the sear.
Figure 6 shows in side and rear view the ejector.
Figure 7 shows in side and rear view the trigger with the stop for the breech
bolt.
In all figures similar letters of reference indicate like parts.
By way of example I have in the annexed drawing shown my improved trigger-
mechanism as applied to a straight or single movement breech bolt of my own
construction, the drawing and the following description however will show that this
trigger-mechanism may be applied to any kind of sliding breech bolt.
A is the breech receiver, A' its tail piece, B. the sliding breech bolt and C the
firing pin with the sear-rest C¹.
The breech bolt is in this case provided on its lower side with the guide ribs c c'
running in grooves a al as indicated in Figure 14, while sear-rest C¹ slides in a
groove a' of the breech tail.
The trigger-mechanism is composed of three parts; the main or central part d
the sear e and the trigger g. Part d rocks upon a pivot at d' and is provided with
an arm dextending rearward and forming the support for arm g₁ of trigger q.
Trigger g is loosely placed in a corresponding cavity in the lower part of the breech
tail and, as just mentioned, rests with its arm g' upon extension d of part d in such
manner, that it cannot drop out or shift. The sear e which is by preference guided
with its lower part es in an opening d' of piece d also rocks at upon d¹ (the pivot
of the latter) and is provided with the sear-edge e¹.
Part d is provided with a recess which by preference is situated at right angles

page_text: e sear opening d³ and which serves
st shank ea of sear e, so as to keep edge e of the
ion. In front the main part d is provided with a projection d' which serv
ent the untimely releasing of the firing pin in the following manner :-
aits normal position the top of projection d stands on the same level with the 5
er surface of a rib or shoulder 6 upon the lower side of the rear part of the
ech-bolt, so that in moving the latter backwards and forwards ribb will slide
r or ride upon projection d. When trigger g is pulled, its arm g¹ finding its
crum in the rear of the cavity of the breech tail in which it is enclosed, presses
wnward upon extension d² of part d whereby the latter is oscillated upon its 10
vot d'. This being situated midway between projection d' and sear e a depression
and e being so fitted together that in this movement
extension d will naturally cause sear e to make a downward and projection d' an
oward movement, the parts
hey cannot alter their position to each other, may in this instance be considered as
ne solid piece.
15
In pushing in or closing the breech bolt, sear rest C₁ of firing pin C encounters
edge e¹ of the sear, whereby the firing pin is arrested, so that when the closing of
the bolt is continued, the firing spring is compressed. From the commencement of
this compression of the firing spring to the complete locking of the breech bolt
there is yet a certain distance for the latter to advance, the length of which depends 20
the degree of compression to be given to the firing spring. The length of this
distance may be seen for example from the difference of length of the firing pin
visible in the rear of the breech receiver in Figs. 3 and 2.
upon
The same or nearly the same distance the shoulder b upon the lower side of the
breech bolt must describe over projection d' of part d, so that when during any part 2
of this movement of the breech bolt the trigger should happen to be pulled, the oscil-
The consequence of this is, that sear e is
lating movement of piece d just described cannot take place on account of projection d
striking against shoulder of the bolt B.
also prevented from making any downward movement, thereby rendering the
releasing of the firing pin impossible.
A releasing and throwing forward of the firing pin in this position in which the
firing spring is already partly compressed, but the bolt not yet completely locked,
might cause the premature firing of the cartridge, which would cause the bolt to
be thrown back and endanger the person handling the gun. Only when the bolt is
completely locked, shoulder b of bolt B will have passed projection and the free
space or recess 6 behind shoulder 6 now permits the raising of projection d' and
thereby also the lowering of the sear, which releases the firing pin. The prope
and last releasing movement upon the sear is effected by preference by the pressin
of nose g³ of trigger-arm g' against the hollowed surface d' of piece d.
The sear nose C of the firing pin, after being released, passes sear edge
almost entirely, and when the bolt is drawn back (opened) again, nose C, t
lower surface of which is for this purpose made slanting, depresses sear e sufficien
for permitting its passage over it. Sear e is thereby oscillated upon its comm
axis with piece d and after nose C' has passed, the former is again brought b
into its original raised position by spring h.
As shewn in Figs. 1, 2, 3 of the drawing the projection or lug g² of trigg
which serves for guiding the latter, passes through the tail piece A¹ and pro
above into the track of the breech bolt, where the said lug g is forked or gro
80 as to permit the passage of shoulder b and sear nose C¹ of the bolt. The
branches of lug g³ are straight in front and stand in such a position as to mee
guide ribs c c (Figs. 1 and 14) when the bolt is pulled back, thus forming a
against the unintentional entire withdrawing of the bolt from the receiver.
rear face of lug g', as will be seen from the drawing, shows a downward and fo
slant and rests against a correspondingly slanting surface in tail piece A' i
manner, that when in opening the bolt, ribs c c strike against the front
the same cannot be depressed by the shock.
с
خط
C
he taken out of the receiver, trigger g must be

page_text: forward, whereby lug is lowered in consequence of trigger arm g' with its
forward end bearing against the top part of its cavity in the breech tail A¹.
With the trigger mechanism just described I combine by preference an ejecting
device, which consists of a lever f movably attached to the forward part of
trigger-piece d. Piece is for this purpose by preference provided with hole
and piece d with hole de through which a suitable pin is passed which forms the
pivot for the ejector f. Piece f is provided in front with the nose f' reaching into
the breech receiver in which position it is held by a suitable spring. I employ for
this purpose by preference the already described trigger-springh situated in part d,
and which consequently is made to bear against part d in one direction and against
part in the other. Nose f¹ of piece fin its natural position under the influence
of spring projects into the track of the breech bolt in the receiver but is kept
depressed by the latter as long as the same is entirely or partly closed. In the
locked position of the bolt, shoulder of the latter stands just above nose f¹ and
therefore this shoulder must be provided with a proper groove to permit the
passage over nose f¹. Nose f' remains immovable until the bolt has been almost
completely opened, when the cartridge or shell withdrawn by the bolt is to be
ejected. In order to permit ejector f to operate, the breech bolt or its head is
provided in front with a slot 63 which is deep enough to permit the entrance or rising
of nose into the track of the bolt or, (which is the same thing) into that of the
receding cartridge or shell. The position of slot is such that nose f¹ is permitted
to rise under the influence of spring immediately before the breech-bolt has
terminated its rearward movement, so that the cartridge strikes with its bottom
against nosef and as it is still pulled back a short distance by the bolt, it is thus
tipped up and thrown out of the receiver.
Thus nose f¹ here acts the part of the otherwise rigid and stationary ejecting
lug in other systems. As a matter of course the trigger mechanism described can
be used with or without the ejector, or with a fixed stop.
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 fire-arms with sliding breech bolt, a trigger-mechanism, consisting of the
trigger loosely placed in the gun, having an arm gl and if necessary a guide
lug in combination with the rocking piece d supporting the arm g, and to which
sear e is movably attached, the piece d being provided with a projection d*
preventing a releasing movement of the sear by striking against the breech bolt
until the latter is completely locked, when projection d' can enter into a suitable
recess in the breech bolt; a spring serving to keep the parts in position,
substantially as described.
2. In trigger mechanisms of the kind specified in the preceding claim a lug g*
attached to trigger g and reaching through the breech tail into the track of the
breech bolt for which it forms a stop to limit its rearward movement, substantially
as described.
3. In trigger mechanisms of the kind specified in the first claim an ejector f
movably attached to piece d and continually pressed upward by a spring h, so that
nose of the said ejector may enter a recess b' of the breech bolt when the
latter is withdrawn, substantially as described.
Dated this 25th day of August 1891
ABEL & IMRAY,
Agents for Applicant.