Grenade Launcher

A grenade launcher is a weapon that fires a specially-designed large-caliber projectile, often with an explosive, smoke or gas warhead. Today, the term generally refers to a class of dedicated firearms firing unitary grenade cartridges. The most common type are man-portable, shoulder-fired weapons issued to individuals, although larger crew-served launchers are issued at higher levels of organisation by military forces.

Grenade launchers can either come in the form of standalone weapons (either single-shot or repeating) or attachments mounted to a parent firearm, usually a rifle. Larger crew-served automatic grenade launchers such as the Mk 19 are mounted on tripods or vehicles.

Some armored fighting vehicles also mount fixed arrays of short range, single-shot grenade launchers as a means of defense. These devices usually fire smoke grenades to conceal the vehicle behind a smoke screen, though can also be loaded with chaff, flares, or anti-personnel grenades to repel infantry attacks. Vehicle-mounted smoke grenade launchers are also known as smoke dischargers.

The earliest devices which could conceivably be referred to as grenade launchers were slings, which could be used to throw early grenado fuse bombs. The ancestors of modern ballistic grenade launchers, however, were simplistic muzzle-loading devices using a stake-like body to mount a short, large-bore gun barrel into which an explosive or incendiary device could be inserted; these were later refined into shoulder-fired blunderbuss-like firearms referred to as "hand mortars". These weapons were not highly regarded due to their unreliability, requiring the user to ignite a fuse on the projectile before firing and with a substantial risk of the explosive failing to leave the barrel; attempts to ignite the fuse on firing using the gunpowder charge resulted in weapons that would often force the fuse into the grenade and make it explode in the barrel.

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