The round is designed to be effective at penetrating windows, blowing up doors, producing casualties in groups of enemies, destroying bunkers, and damaging or disabling soft-skinned vehicles. The M203 grenade launcher is intended to be used as close fire support against point and area targets. The M320 features an advanced day/night sight, a double-action firing mechanism (as opposed to the M203's single action) as well as other benefits such as an unobstructed side loading breech. Marine Corps, Air Force, and Navy will continue to use the older M203. when the target is at close range or near friendly troops), an under-barrel system has the advantage of allowing its user to also carry a rifle, and to easily switch between the two.Ī new grenade launcher, the M320, will eventually replace the M203 in the United States Army. Because the size and weight of the 40mm ammunition limits the quantities that can be carried on patrol, and because because a grenade is often not an appropriate weapon for a given engagement (i.e. However, while the M79 was a stand-alone weapon (and usually the primary weapon of troops who carried it), the M203 was designed as an under-barrel device attached to an existing rifle. military forces during the early 1970s, replacing the older M79 grenade launcher and the conceptually similar Cold XM148 design. The M203 has been in service since 1969 and was introduced to U.S. The M203 was the only part of the army's Special Purpose Individual Weapon (SPIW) project to go into production. The version fitted to the Canadian C7 has a sight attached to the side of the launcher, either on the left or right depending on the user's needs. a separate sighting system is added to rifles fitted with the M203, as the rifle's standard sights are not matched to the launcher. The rifle magazine functions as a hand grip when firing the M203. The device attaches under the barrel, the launcher trigger being in the rear of the launcher, just forward of the rifle magazine. Stand-alone variants of the M203 exist, as do versions designed specifically for many other rifles. The launcher can also be mounted onto a C7, a Canadian version of the M16 rifle which requires the bottom hanguard on the rifle to be removed in order to mount the launcher. Though versatile and compatible with many rifle models, the M203 was originally designed for the U.S. It uses the same rounds as the older standalone M79 break-action grenade launcher, which utilize the High-Low Propulsion System to keep recoil forces low. The M203 is a single-shot, 40mm grenade launcher designed to attach to a rifle.

Mosin nagant grenade launcher