摘要 |
In e.g. a projectile launcher, an arresting sleeve (12) absorbs energy by deformation, which is necessary to arrest a piston (15) from which a counter-mass or a projectile is ejected. The counter-mass (17) should be dispersed as rapidly as possible on exit, in order not to endanger those in the vicinity of the gunner. According to the invention the arresting sleeve (12) has annular peripheral grooves (13,14) on its outer face and also on its inner face of equilateral triangular cross-section, and the piston (15) has a cartridge (16) holding the counter-mass (17), which at its forward end has a greater wall thickness than at its rearward end. |