GB543737A - Improvements in or relating to projectiles for cannons or the like - Google Patents

Abstract

543,737. Ammunition projectiles. DUYNSTEE, A. W. T. J., and POSSEN, L. H. May 8, 1940, No. 8313. [Class 9 (i)] A projectile is provided with a rear extension containing a chamber filled with a powder charge which is fired as a direct or indirect consequence of the explosion of the main charge in order to assist the propellant and even out the peak pressure within the gun barrel, the chamber being closed by a disc the rim of which has besides a cylindrical part, a conical or extended cylindrical part forming a gas-tight fit with a correspondingly shaped opening in the end wall of the chamber. In one form an extension 2 screwed on the rear end of the projectile, has a chamber 3 closed by a disc 4 having a gas-tight conical seating upon a flange 5. A cylindrical extension 13 on the disc 4 is guided by a ring 17 which acts as a guide for the extension 13 and an abutment for the disc 4 when blown outwards by the explosion of the charge in the chamber 3. A spring 18 normally keeps the disc 4 seated. The ring 17 is supported by three bars, of which one is shown at 15, extending from a ring 14 screwed beneath the flange 5. A casing 6 screwed into the disc 4 houses a detonator 8 held in position by a spring stirrup 9, the detonator moving by inertia against a firing pin 12 when the gun is fired. Alternatively the detonator may be fixed and the firing pin movable by gas pressure as the main charge is fired. In a modification a fixed firing pin and movable detonator are mounted on the base of the projectile, and in another form a fixed detonator on the base is struck by a movable pin mounted on the disc 4. The seating of the disc 4 may have a cylindrical extension above the cone, or a stepped cylindrical closure may be used. A tubular member extending beyond the ring 17 may be screwed to the extension 2 so that the cylindrical extension 13 of the disc 4 does not project when the disc 4 is blown outwards against the ring 17. The invention may be combined with an arrangement in which the gases escape through inclined bores to cause rotation about the longitudinal axis.