Abstract: A training cartridge projectile comprises: a plastic housing having a prishaped axial recess of hexagonal cross-section, closed at the rear and open at the front; a heavy piston of similar shape slidable in the recess; a cup-shaped plastic ogive member having its open end attached to the open end of the housing to form a dye cavity and comprising an annular weakening groove; spring means between the ogive member and the piston; and a mass of aerosol-producing dye material in the dye cavity adapted to be disseminated by the forward motion of the piston in the projectile on impact with a target.