Breech block and chamber for artillery weapon

摘要

A breech chamber (3) fits into a space defined between a pair of side portions (4,5) of the breech block (6). Lateral lugs (9-12) formed on the breech chamber include bearing surfaces (13-16) facing rearwardly, which engage complementary surfaces (18-21) of recesses (22-25) in the breech block.The complementary pairs of bearing surfaces are oriented such that the plane of each of them intersects a median plane coincident with the axis (26) of the barrel at an angle greater than 90?. The angle of intersection (A2) of the rearmost of the pairs of surfaces may be slightly greater than that (A1) of the forward pairs. The bearing surfaces are symmetrical about the median plane.