 The design criteria were that the gun would have a muzzle velocity of ; that the tube would weigh only instead of the conventional for a tube with that energy; that, as a consequence it would be made of alloyed steel; that it should have a maximum breech pressure of ; and that it should have three independent primers.Because it would need to be fired only once, the barrel could be made lighter than the conventional gun.Nor did it require rifling or recoil mechanisms.