Women Ordinance Workers (WOW) fire heavy machine guns in Aberdeen proving ground, MD, USA. Explosions on the ground. West point cadets visit Aberdeen proving ground. Small rocket launcher demonstrated for the west point cadets.
Medium tractor on proving ground, Aberdeen. Medium tractor T-31 moves over muddy terrain. Tractor moves over terrain with and without 4.5 caliber gun on M-1 carriage.
Mortar carrier T-21 circles the field at Aberdeen proving ground. It moves over rough and level terrain. Soldiers open rear door revealing mortar. Soldier climbs into the carrier and inspects grenades and other equipment. (Note: The 4.2" M2 heavy mortar recoil was hard on the halftrack chassis so the T-21 was cancelled and never adopted.)