GB937658A - Improvements in or relating to air guns - Google Patents

Abstract

937,658. Air guns. BIRMINGHAM SMALL ARMS CO. Ltd. May 20, 1960 [May 19, 1959], No. 16880/59. Class 119. A piston and buffer assembly for an air gun comprises a substantially tubular piston formed at one end with a plate having an aperture receiving an anchoring part of the buffer, the anchoring part and the aperture being freely separable but being so arranged that when the assembly is inserted into the cylinder of the gun, such separation is prevented by the engagement of the piston and buffer with the cylinder. In one form the plate 9, Figs. 1, 4, is secured at one end of the piston 1 and has an aperture 10, 11 shaped and located as shown. The buffer comprises an air-sealing washer 3, a metal washer 4, a resilient washer 5 of oil-resistant rubber or plastic and a second metal washer 6, all mounted on a stud 2 formed with a reduced reduced portion 7 and a head 8. To anchor the buffer to the piston, the head 8 is passed through the outer portion 11 of the aperture and the buffer moved radially so that the reduced portion enters the central portion 10 of the aperture, the head 8 preventing axial withdrawal through this portion of the aperture. On insertion of the assembly into the cylinder (not shown), the buffer cannot move radially with respect to the piston and is thus securely anchored thereto. In another form the piston and buffer are of substantially square crosssection with a raised rib 19, Fig. 9, along its upper surface. The plate 28 is formed with a central aperture 29 having extensions 30 forming a slot adapted to receive the flat head 26, Fig. 11, of the buffer stud which is shaped as shown. The head 26 is passed through the slot of the plate and the buffer then turned through 90 degrees to engage the head 26 behind the plate 28 and to bring the buffer into alignment with the piston. In this position the buffer is anchored to the piston against axial removal and since the piston and buffer are non-circular, when the assembly is inserted into a complementary cylinder of the gun, the buffer cannot rotate relative to the piston and is thus anchored. The pistons in both embodiments are formed by pressing or like operations from a suitably shaped blank of sheet metal, slots being punched out for slidably receiving the cocking lever of the gun and for forming a bent for engagement by a sear of the gun action.