Abstract: The invention is an improved solid propellant grain, wherein the solid prllant grain is structured to provide a programmed method and system for splitting the solid propellant grain at a programmed moment to provide an increase in the burning surface. The programmed-splitting of the solid propellant grain provides improved ballistic performance of guns, which yields a higher muzzle velocity for a given projectile without increasing the maximum pressure exerted on the gun chamber. The improvement consists of embodiments that are a plurality of slits of various configurations through the longitudinal length of each grain of solid propellant. The improvement includes a structure to delay end burning of the grains until the longitudinal exterior surface burns sufficiently to split the grain into a plurality of sections at a programmed moment when the increased burning surface is desired to occur.

Abstract: A one-piece sabot of the can type comprises an energy storage means posited between the obturator and the aft end of the subcaliber projectile and means for mounting the sabot on the projectile in one of a plurality of axial positions. Energy stored in the storage means during the initial phase of launch is released after launch to effect projectile-sabot separation.