Riot gun

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.

Less-lethal launchers can fire various sorts of ammunition:

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 [1] [2].

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 metres (33 yards). This method is best used by operators wearing gas masks, as the chemical agent can easily be blown towards the operator.

These are also called gas grenades, and are used at longer ranges. They are analogous to rifle grenades, providing increased accuracy and range over hand-thrown gas grenades. Gas grenades may be used by operators without gas masks, as the agent is only dispersed in the area of impact, as far away as 150 yards (140 m). The agent in gas grenades is dispersed as a gas or an aerosol spray.

These are specialized gas grenades designed to penetrate light barriers, such as windows, hollow core doors, and interior walls, and disperse chemical agents on the far side.

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