GB757640A - Improvements in or relating to silencers and/or flash eliminators for firearms - Google Patents

Abstract

757,640. Silencers and flash eliminators for firearms. PATCHETT, G. W. Oct. 19 1954 [Feb. 22, 1954], No. 5206/54. Class 92 in a nrearm, e.g. a light automatic weapon, the noise and flash of discharge are eliminated by the provision of spaced sets of holes 12, 13, 14, Fig. 1, along the barrel 11 which open into annular passages formed by two spaced tubes 15, 16 surrounding the barrel so that the flow of explosion gases is repeatedly reversed before passing to atmosphere and a movable obturator at the muzzle end of the barrel comprisises two pivoted shutters 45 adapted by means initiated by movement of the breech block successively to unseal the muzzle for the passage of a projectile and to seal it immedately after passage thereof so as to prevent the gases emerging from the muzzle. On passing through the holes 12, 13, 14 the gases are deflected rearwardly by lugs 24, 25, 26 through the inner annular passage 17 and are then deflected by a plate 29 through apertures 28 into and forwardly through the outer annular passage 18 containing a helically wound length of strip metal 30 or a series of split and spread washers. The outer tube 16 which has a heat insulating lining 20 of asbestos, has an extension 37 projecting beyond the muzzle and surrouding the shutters 45 and formed with channels 43, Figs. 1, 7, terminating in aperture 44 disposed opposite holes 35 in a ring closing the forward ends of the annular passages 17, 18. The gases, after passing through the helical path in the annular passage 18 emerge through aperture 35, 44 to atmosphere. The shutters 45 are of channel section and the flanges at one end straddle a square block 46 secured over the muzzle and are pivoted thereto by screws 47. Rubber closure strips 65 are scured to the forward ends of the shutters which are urged towards each other by a spring 63 and are connected by tooth gearing. Movement of the shutters to open position is effected by a lever 53 pivoted at 54 on the extension 37 and engaging at one end with the lower shutter 45, the other end being engaged by one end of a rod 55 in a guideway 56; the other end of the rod 55 is engaged by a pivoted cranked lever 58 firmed with a projection or roller 60 projecting through a slot 61 in the breech casing 9 so as to lie in the path of movement of the breech block 62. On forward movement of the breech block 62 for firing the rod 55 is moved to the left, swinging the lever 53 and opening the shutters and on recoil of the breech block beyond the roller 60, the spring 63 closes the shutters again. Instead of the shutter 45 being moved to this closed position by the spring 63, the explosion gases may be used to operate another push rod engaged by a plunger in a small cylinder communicating with the breech end of the barrel.