Break-joint gun has breech block between barrel unit and end wall of bascule which moves in straight slide on bascule and grips support surface on barrel when gun is unbroken, spring between end wall and breech block biasing it forward

摘要

The break-joint gun has a breech block (12) positioned between the barrel unit and the end wall (4) of the bascule (5). This moves in a slide (24) on the bascule and when the gun is unbroken it grips a support surface (14) on the barrel. The slide is straight and coooperates with a guide pin (23) on the breech block. a spring (27) between the end wall and the breech block biases it forward. The foot (12) of the block engages with a second support surface (38) on the barrel and is supported by a slide surface (16) in the bascule. A stop (17) limits the forward movement of the block over this surface.