Patent GB-154611-A (GB)
Title: Improvements in and relating to fire-arms
IPC: F41A15/14
Filed: 1919-10-08
Abstract: 154,611. Pedersen, J. D. July 30, 1915, [Convention date]. Breech actions, slidin breech-block; indicating when loaded, means for; stocks. - Relates to automatic or semi-automatic firearms in which the breech mechanism is operated by the rearward kick of the cartridge case acting upon a momentum slide, and consists (1) in a detent adapted to lock the breech-block in the closed position, and adapted to be retracted by the operation of the firing-mecruanism, said redaction serving- simultaneously to depress the trigger so that it cannot reengage the sear; (2) in a spring control-device for the detent which also serves as a sear-spring; (3) in a grip safety-device co-operating with the breech-block detent; (4) in an adaptation whereby the detent mav hold the breech mechanism in the rearward position for handactuation after each shot. The invention is shown as applied to the automatic pistol described in Specification 133,695. The sear S is pivoted at 17<a> in the frame B, and carries cocking-shoulders 17<b>, Figs. 14 and 17, adapted to snap into notches 8j in the hammer H when this is depressed by the roller 3<c> on the recoiling momentum slide C, and noses 17d adapted to be pressed rearwards by the face 6n of the trigger F to rotate the sear out of bent and release the hammer. The trigger F is slotted through so as to embrace the magazine, and its finger-piece is bored to receive a trigger-spring 6e co-operating with a lever f pivoted at 6j to the trigger, and engaging a notch in the frame B. This device tends to urge the rear end of the trigger upwards. The forward movement of the trigger is limited by the engagement of shoulders thereon with the forward ends of the slots 2t in the frame. To lock the breech-block in its forward position, and to disarm the weapon during the operation of the breech mechanism, a detent N, shown detached in Fig. 16, is slidably or pivotally mounted in the frame, and co-operates at its lower end 14b with the trigger in such a manner that the trigger may be moved longitudinally independently of the detent, but is compelled to rise or fall therewith. A spring 14m is mounted in the detent, and is actuated through a pivoted lever n by a shoulder 17<c> on the sear; it serves the twofold purpose of urging the detent upwards and the sear against the hammer. This control spring is so arranged as to offer a considerable initial resistance to the pull on the trigger, the resistance decreasing as the trigger is retracted. In the forward position of the slide C, an inclined nose 14d on the detent N engages an incline 33d on the slide, and locks the breech mechanism in the closed position. This locking nose 14d may, if desired, be omitted. The sear is provided with shoulders 17f engaging faces 14e on the detent, so that when the trigger is pulled, the sear partially depresses the detent. The depression is completed on release of the hammer by cam faces 8<k> thereon co-operating with faces 17<n> on the sear. The trigger is thus depressed out of engagement with the sear noses 17d, and is maintained in that position so long as the detent is held down by the member e of the breech-block during the recoil and return movements of the breech mechanism. Moreover, if the pull on the trigger is maintained, a succession of shots is prevented, for the sear is free to snap into bent when the hammer is depressed into the cocking position, since the sear noses 17<d> may enter the notch 6<m> in the rear end of the trigger. Thus, when the slide has returned to its forward position, the detent may rise into the locking position, but the sear can be released from the hammer only by releasing and re-pulling the trigger. The inclination of the co-acting faces 14d and 33d of the detent and slide may be such as to offer only a temporary resistance to the recoil of the breech mechanism in the case of a premature explosion of the cartridge, or in the case in which the slide is retracted by hand; and the inclination of the detent in the frame is such as to diminish any abnormal pressure and consequential frictional gripping between the co-acting faces 14d and 33d during a premature explosion. A grip safety device comprises a member G carrying the hammer-spring bearings 7<b> and 8<m>, and pivoted to the frame by a removable pin. The design is such that when the hammer is cocked, the line joining the pivotpins g and 8<a> lies forwardly of the bearing 8<m>, and the member G is therefore pressed rearwardly by the spring 8<e>; and when the hammer has fallen, the said line lies rearwardly of the bearing 8<m>, and the member G is pressed forwardly. The position of this member thus indicates whether the hammer is cocked or not. When the member G is in its normal rearward position, prongs 7f, Figs. 3 and 9<a>, thereon, rest beneath projections 14<c> on the detent N, and prevent its downward movement. Thus, if the trigger is pulled, the hammer cannot fall, owing to the wedging of the cam surfaces 8<k> of the hammer against the sear, and the engagement of the sear noses 17<b> with the faces 14<e> on the locked detent N. When the weapon is gripped, the member G moves into its forward position, and the prongs 7f are moved out of engagement with the faces 14<c>. This action unlocks the firing train and permits the weapon to be fired, whereafter the member G is locked in the forward position by the depression of the projections 14<c> on the detent into the recesses 7<j> in the member G. The detent N may be employed to lock the breech mechanism in its open position by manually withdrawing the slide C into its rearmost position, and allowing the detent to rise in front of the face 5<m> of the breech-lock (Fig. 9<a>). On releasing the grip, the member G moves into its rearward position, and locks the member N from downward movement. The breech mechanism may be released by simply gripping the weapon, which causes the return-spring 4<d>, acting through the slide and breech-block, to ride down the detent N. By employing a weaker slide-return spring, the slide will be held in the open position in this manner after every shot, provided that the trigger is released immediately, and can be returned to the firing position only by pulling the trigger again. A modification of the firing and safety mechanism is shown in Fig. 35, in which the hammer H<2> is integral with the rod 8<b>, and acts on the firing-pin P through a lever L<2> pivoted to the slide C. The hammer is depressed by this lever on recoil of the slide, and is guided downwards by a roller 8<p> pivoted to the frame B until the hook 17b on the sear S snaps into the cocking notch 8<j> on the hammer. The means for depressing the detent N out of engagement with the slide on the fall of the hammer consists of a lever co-pivotal with the sear and having arms s<10>, s<12> engaging respectively the face 14e on the detent and a lug 8<k1> on the hammer. The detent N is pivotally connected by a link L<4> to the frame B, and the grip safety G is arranged to co-operate with the foot of the detent, the arrangement being operatively the same as that already described. A further modification is described in which the lever controlling the detent is mounted on a separate pivot below the sear, and in which a separate spring is employed to urge the detent into its locking position. In another modification, the upper end of the detent does not co-act directly with the slide C, but pushes up a lever pivoted to the frame into engagement with the slide. The Specification as open to inspection under Sect. 91 (3) (a) comprises also (1) a barrel D mounted in the momentum slide C so as to .remain immovable relatively to the frame B when the slide recoils, (2) a pivoted extractor 5<a>, (3) a magazine catch m, Fig. 3, and (4) stock-plates on the sides of the grip, held in undercut lips and secured bv the pin g. This subject-matter does not appear in the Specification as accepted.