Wad and slug for a shotgun cartridge

Claim 1

A wad for a shotgun cartridge having a case with a primer and powder therein, to be used with a slug which is held in the case by a crimp provided on the case and which has a diameter dimensioned such that an annular gap is provided between the inside surface of the case and the slug, said wad being located in the case between the powder and the slug, wherein said wad comprises: a substantially solid cylindrical body having a longitudinal axis, front and rear end faces, a cylindrical side surface, and an outside diameter smaller than the inside diameter of the case; said cylindrical body including a plurality of independent, symetrically-located blind holes which extend a predetermined relatively shallow distance thereinto parallel to and spaced from the longitudinal axis of the body, from the rear end face of the body adjacent to the powder; means circumferentially attached about the cylindrical side surface of the body adjacent to the rear end face to define a continuous gas seal for preventing escape of explosive gas produced by combustion of the powder along the cylindrical side surface, and for centering the rear end face coaxial with the case; said body further including a plurality of independent, non-radial and separate restriction passages individually connected to the blind holes and which extend perpendicularly to imaginary planes including the axes of the associated blind holes and the axis of the body to open to the cylindrical side surface of the wad body adjacent to said circumferential seal means so as to give a rotational torque in the same predetermined direction to the wad body when the explosive gas is discharged from the restriction passages; said body being provided, on the portion of the cylindrical side surface adjacent to the front end face thereof, with a plurality of independent, segmental projections; male and female connection means for coaxially and snugly connecting the wad body and the slug; and means for transmitting rotation of the wad body to the slug.