M3 37 mm Anti-Tank Gun

Introduced in 1940, this was the first dedicated anti-tank gun U.S. forces fielded in significant numbers. It was also widely used in the infantry support role, firing high-explosive and canister rounds, with a barrel length of 2.1 m, or 6 ft 11 inch (L/56.6). While it was a standard anti-tank gun of the U.S. infantry, the continuing improvement of German tank armor rendered the 37 mm ineffective. By 1943, the more powerful British-developed 57 mm gun M1 gradually replaced the 37 mm in the European and Mediterranean theaters. In the Pacific the M3 remained in service until the end of the war. American industry produced 18,702 units between 1940 and 1943. The Stuart Light Tank M3/M5, the Lee Medium Tank M3, and Greyhound Light Armored Car M8 all used variants of this gun. This gun was also mounted on a variety of other vehicles to create self-propelled anti-tank units.