The M3 GMC was the first significant variant of the M3 Half-track. It was developed during 1941 as a temporary measure to fulfill the Tank Destroyer role.The development model (known as the T12) was modified to carry the M1897A5 75mm field gun, a gun of French origin, which proved itself one of the best guns from WWI. Though a somewhat dated design it was still considered a capable gun and trials went ahead and, in July 1941, the design was accepted by the US Army.The new vehicle was designated 75mm Gun Motor Carriage M3 on 31 October 1941. Initially the shield was the small original gun shield but this was soon replaced in 1942 by a more substantial shield offering the crew better protection. It saw its first combat service in the Philippines in December 1941. The bulk were allotted to the Tank Destroyer units and these saw service with the US forces in North Africa. During “Operation Torch” the M3 GMC saw extensive action, being used as Tank Destroyers, close support weapons and assault artillery. They tended to be used for any job the commanders saw fitted and did none of them well. Their most famous moment came in March 1943 when M3 GMCs of the 601st Tank Destroyer Battalion repulsed an attack on the 1st Infantry Division by the 10th Panzer Division at El Guettar. They destroyed over 30 German tanks, losing 21 of their M3 GMCs in the process.Some saw action during “Operation Husky”, but by the time the Italian campaign was in full swing most had been replaced in the front line by the superior M10 Tank Destroyer.
