GB127278A - Improvements in Automatic Repeating Firearms. - Google Patents

Abstract

127,278. France, State of. July 11, 1916. [Convention date]. Machine guns.-Relates to automatic rifles and machine guns of the long barrel-recoil type and consists in a special construction of breech mechanism and cartridge-feed mechanism. Trigger mechanism adjustable for single shot or continuous firing, and a special construction of casing and frame are also described. The invention is shown applied to a gun of the kind described in Specification 127,275, [Class 119, Small-arms], in which the gas pressure upon the front edge of the barrel aids the recoils. The rotary bolt 16 is operated by a non-rotary sleeve 15 having helical slots 41, Fig. 5, engaging studs 39, Fig. 6, on the bolt. In the unlocked position the sleeve is locked to the bolt by a stud 45, Fig. 2, mounted in a radial recess in the sleeve and having a bevelled end engaging a corresponding recess in the bolt. When the sleeve is retracted, the stud 45 is moved into its locking position, shown in Fig. 2, by an incline on the barrel extension 14, and is then held locked, as shown in Fig. 2, and is not free to move outwards to release the sleeve from the bolt, to allow of the locking-movement, until the sleeve has moved forwards to bring the stud opposite the ejection opening. The cartridges are pushed forwards from the magazine by a projection 31, Figs. 1 and 3, on a block 22 fixed to the bolt sleeve, the noses of the cartridges riding up an inclined block 78 into the barrel. The block 78 is pivoted and is, when the bolt approaches its forward position, rocked downwards, as shown in Fig. 3, to allow the pusher 31 to pass. In front of the block 78 is a pivoted spring catch 79 adapted to engage a recess 90 in the barrel to prevent the barrel from rebounding. The catch is automatically disengaged by the feeder 31, as shown in Fig. 3, when the breech is locked. The trigger mechanism comprises a sear 30, Fig. 4, adapted to engage the block 22 to hold the breech open, a trigger 58 and sear-actuating mechanism comprising a link 64, a lever 60, and a catch 62 pivoted to the lever 60. There is also a cam or adjustable stop 70 for adjusting the mechanism for single shots or for continuous firing or for locking it at safety. In the view shown in Fig. 4, the mechanism is adjusted for single-shot firing, the stop 70 being turned down and the trigger pulled. The pull of the trigger turns the catch 62 which at the top abuts against a projection 65 on the barrel extension. This turning movement depresses the pivot 61, thereby turning the lever 60 pivoted at 57 and depressing the sear. If the barrel is not in its forward position the catch does not abut against the projection 65, and the sear is not actuated. After discharge, the catch and lever 60 rise and the catch becomes disengaged from the link 64, so that the trigger must be released and pulled again for the next shot. When the stop 70 is turned half round, the link 64 rises and does not become disengaged from the catch 62, which is then turned to depress the sear by the projection 65 on the barrel extension. When the stop is turned right up, the lever 60 is locked. The casing and frame comprises a cylindrical portion 1, 2, Fig. 1, which may be composed of drawn tubing and two stayed cheeks or side plates 7, 8, Figs. 1 and 2, connected to the tubes in a readily removable manner. The recoiling parts are maintained in their angular position by a block 22 fixed to the bolt sleeve and passing through slots in the barrel extension 14 and casing 2. The return springs 18, 19 of the barrel and breech-bolt are arranged concentrically in the rear of the casing and bear upon the rear closing-plug 6 of the casing.