The M32 Grenade Launcher, Multi-shot, 40mm was considered for procurement by the US Marine Corps in 2005, based on needs assessment in Iraq. The requirement called for a grenade launcher that could rapidly fire multiple rounds, unlike the single shot M203 Grenade Launcher and M320 Grenade Launcher. The MGL-140, manufactured by Milkor USA Inc., was evaluated and tested. Based on the test results, the USMC issued specifications for modifications to meet Marine requirements. In August 2005, the USMC awarded a contract to Milkor for weapons meeting the improved design, designated the M32 Multiple shot Grenade Launcher (M32 MGL or M32 MSGL). Delivery was completed by early 2006.
The M32 MSGL is an awkward looking weapon, stripped down for its basic function of putting low-velocity 40mm grenade cartridges downrange, on target. It features a collapsible buttstock and a Picatinny rail with an M2A1 reflex sight mounted. Using a mechanical concept very much like a revolver pistol, the M32 will fire six rounds as fast as the operator can pull the trigger. The reloadable six-round magazine can then be quickly recharged and reloaded to fire six more rounds.