During WWII, the U.S. Army used a series of grenade projection adapters that converted hand-grenades into rifle grenades. For the M1 Garand the device was designated as the M7. This hollow-tubed, muzzle adapter could throw a standard Mk 2 grenade up to 220 yards, compared with the maximum of 33 yards when it was thrown by hand. To launch a grenade, a special high-powered blank cartridge was chambered in the rifle. Once the device was fixed to a blank-loaded rifle, it could fire fragmentation, anti-tank, and smoke grenades, as well as pyrotechnic signals. One to three M7 grenade launchers were issued to each rifle squad depending on the period of the war.