Background
As the United States found itself drawn into World War II, it was clear to Army commanders from the outset that their standard 37mm anti-tank guns were obsolete in the face of German armor. Pressed for time to field a suitable replacement, the British 6 pounder was adapted to the needs of the US Army. Although considered too heavy by many elements of the US Army, and limited to primarily armor-piercing ammunition, the M1 eventually became the standard anti-tank gun of American infantry divisions by 1944. The type saw action with American, British, Russian, and Free French forces by the end of WWII, and was phased out in the early 1950’s, although some smaller armies still have examples still in service.