The Projector, Infantry, Anti Tank (PIAT) was a spigot mortar developed by the British in 1941 as a replacement for the obsolete Boys anti-tank rifle, and issued to field units in 1943. While difficult to use, the weapon was capable of throwing a two-and-a-half pound bomb with a HEAT warhead anything up to 330 yards. The weapon used a large coil spring fired spigot, which was used to ignite the bomb's primer and thus the propellant charge.