This article is about the less-lethal launcher. For the shotgun, see riot shotgun.
This article contains weasel words: vague phrasing that often accompanies biased or unverifiable information. Such statements should be clarified or removed. (March 2009)
A U.S. Marine holding an American model M-32 6-shot 40 mm launcher, which can be used as a grenade launcher or riot gun depending on the ammunition used.
In current usage a riot gun or less-lethal launcher is a type of firearm that is used to fire “”non-lethal” or “less-lethal” ammunition for the purpose of suppressing riots. Less-lethal launchers may be special purpose firearms designed for riot control use, or standard firearms, usually shotguns and grenade launchers, adapted to riot control use with appropriate ammunition. The ammunition is most commonly found in 12 gauge (.729 inches) shotguns and 37mm and 40 mm (1.46 and 1.57 inches) grenade launchers.
In the United States, the term riot gun more commonly refers to a riot shotgun.
1.1 Chemical agent ammunition
1.1.1 Muzzle dispersion
1.1.2 Canister projectiles
1.1.3 Ferret rounds
1.2 Impact rounds
1.2.1 Baton rounds
1.2.2 Beanbag rounds
1.2.3 Rubber buckshot
1.2.4 Pepperball rounds
2 Types of less-lethal launchers
3 Legal issues
7 External links
Less-lethal launchers can fire various sorts of ammunition:
Impact projectile. These rely on kinetic energy, e.g. rubber bullets.
Teargas cartridge, chemical riot control agent.
Pepper spray, chemical riot control agent.
Sound 180db Sound emitting electric Projectile
GLIMPS (Grenade-Launched Imaging Modular Projectile System). This is a 40 mm caliber projectile which contains a small camera which transmits television images of what it sees.
To avoid breaking the projectile up, less-lethal cartridges are often propelled by black powder, which when fired may make an eruption of sparks and smoke which is spectacularly large to those accustomed to modern cartridges propelled by more modern propellants: see images at  .
Chemical agent ammunition
Chemical agents may be dispersed in three ways:
This method is the simplest: the chemical agent is in the form of a loose powder, which is expelled by the propellant of the cartridge. These rounds are used at short range, and have effect from the muzzle to a range of about 30 met