A plurality of generally disclike elements are unitarily arranged in stacked, face contacting relation within a cartridge. The projectile element edges are formed into a set of teeth or projections for cooperation with similarly dimensioned toothed tracks to produce element rotation for movement along guide grooves extending longitudinally within a gun barrel. As a further aspect, the guide grooves are fanned out a predetermined amount in the region immediately adjacent the muzzle to produce a prescribed element dispersion.