XM174 grenade launcher

The XM174 is a mounted automatic 40mm grenade launcher heavily based on the M1919A4 machine gun and the M79 grenade launcher, but fed from an ammo can. It was used in the Vietnam War as a tripod mounted crew-served weapon and as a weapon mounted on various vehicles and aircraft. The XM174 has the same fire control group as the M1919A4.

XM174
Type	Automatic grenade launcher
Place of origin	United States
Service history
Used by	US Army/USMC, USAF
Wars	Vietnam War
Production history
Designed	1968
Manufacturer	Aerojet Ordnance Manufacturing Company
Specifications
Mass	7.25 kg
Length	712 mm
Cartridge	40x46 mm
Action	Recoil
Rate of fire	350RPM
Feed system	12 Round Drum Magazine
Sights	Iron

The ammunition was held in a drum canister with a maximum capacity of twelve 40 mm rounds. The launcher was also capable of semi-automatic fire.

U.S. Air Force Security Police personnel in Vietnam were also issued the XM174 automatic grenade launcher which was often used on perimeter defense posts and heavy weapons vehicles.[1]