GB616629A - Improvements in or relating to breeches for guns - Google Patents

Abstract

616,629. Ordnance. VICKERS-ARMSTRONGS, Ltd., HESELTINE, J. C. W., and BARRETT, R. H. Sept. 12, 1946, Nos. 27452 and 37296. [Class 92 (ii)] The breech mechanism of a gun is carried by a breech ring 1 which is mounted on a barrel ring 2 for eccentric rotation with respect to the barrel 3 for opening and closing the breech, the extent of rotation of the ring being normally limited by the engagement of a pivoted stop catch, Fig. 8, with fixed stops 45, 46, but the arrangement being such that the catch may be moved clear of the stop 46 so that the breech ring may be further rotated and removed from the barrel ring as by unscrewing. The stop catch shown is pivoted at 41 and has two arms 40a, 40b of which arm 40b is urged inwards by a spring 43 to bring a projection 40c on the arm into the path of the two stops. Finger pressure on a part 40d of arm 40a enables the projection to move clear of the stop 46. The breech ring is rotated between its open and closed position by a handle 9 fitted with a spring-controlled pivoted lever for actuating a locking plunger. When the breech ring is rotated from the closed position shown to the open position, a roller 14d, Fig. 2, on a threearmed cocking lever engages with a cam 22 on the barrel ring. This causes the lever to pivot, an arm 14c compressing a main spring 15 and arm 14a retracting the striker assembly 13. Coacting with the striker assembly is a trigger sear 17 which slides in an aperture 25 in the breech ring and which is actuated by a firing plunger 50 in the barrel ring. A safety lever 19 pivoted on a stud 28 can be moved to either of two positions, in one of which its arm locks the cocking lever against rotation for firing. The breech ring also carries a pivoted spring- controlled lever 30 formed with a cam surface such that when the breech ring is moved to the, open position this cam will engage with a roller on an extension arm of the pivoted extractors.