Though not technically the first submachine gun deployed in combat, the German army's Machinenpistole 40, or MP40, is certainly one of the most recognizable.
From 1940's-era newsreel clips to just about every World War II movie ever made, the iconic MP40 has become synonymous with the Nazi troops that conquered Europe. Loosely derived from the earlier MP18 which was deployed late in World War I as a trench sweeper for the German army, the MP40 fires a 9mm pistol round out of a nearly 10-inch barrel.
That's a good combo for an accurate, easy to control weapon. Add on a full-length folding stock and the MP40 stands as one of the most devastating submachine guns ever built.
But there's more to it than that. The MP40 had a very heavy bolt that combined with the weapon's auto-only operating system to make for a slow rate of fire that allowed the shooter to control muzzle rise and stay on target.
Watch this operator fire an MP40 and see for yourself how this early submachine gun design withstands the test of time.