MIL-S-63348A, MILITARY SPECIFICATION: SUBMACHINE GUN, 5.56MM, PORT FIRING, M231 (20 AUG 1981) [NO S/S DOCUMENT]

MIL-S-63348A, MILITARY SPECIFICATION: SUBMACHINE GUN, 5.56MM, PORT FIRING, M231 (20 AUG 1981) [NO S/S DOCUMENT]., This specification contains requirements, quality assurance provisions, and packaging for the Submachinegun, 5.56MM, Port Firing, M231.