Abstract: An improved expanding ballistic projectile is disclosed which has an inner core of dense relatively soft, deformable material, and an outer jacket of malleable material. A central axial recess is provided in the nose portion of the inner core and a central opening is provided in the nose of the outer jacket coincident with the recess in the inner core. A generally cylindrical expansion-initiating insert member, having a generally symmetrically tapered rear portion and a generally symmetrically tapered nose portion and of a hardness greater than the inner core, is disposed in the recess. This cooperates with a plurality of circumferentially spaced longitudinal slits formed in the outer jacket to achieve controlled uniform expansion upon impact.