United States 40 Mm Grenades - Less Lethal and Riot Control Cartridges

Less Lethal and Riot Control Cartridges

With the greater emphasis on improving less-lethal capabilities of the U.S. military in response to the changing nature of U.S. deployments around the world, less-lethal and riot control cartridges have been developed over the years. These rounds are often akin to 37 mm cartridges that have been in use by the Law Enforcement community for years. These cartridges are also mainly 40×46mm, as it is likely that a high velocity variant would greatly detract from their less-lethal capabilities.

Oldest of these types is the riot control 40 mm gas cartridges. In the U.S. military the standard CS gas cartridge is designated M651. The M651 has 53 grams of CS mixture. Burn time is 25 seconds, with an area coverage of 120 square meters. The round is effective to 200 meters against point targets and 400 meters against area targets. It is unclear which of the experimental variants, either the XM651 or XM651E1 was standardized, but the differences most likely have to do with the nature of the agent or the type of agent (though the evidence is relatively clear that CN was never used in the XM651).

Older cartridges designed specifically for the M79 grenade launcher or the AN/M8 pyrotechnic pistol also remain in inventory. The XM674/M674 is a CS riot control agent cartridge. The unit contains 90-100 grams of CS mixture, with a 2-7 ignition delay and burn time of 10 to 40 seconds. The round is effective to a distance of 65 to 90 meters. It can also be hand fired.

More recent have been a variety of canister rounds and other less-lethal projectiles. The M1029 contains 48 rubber balls of .48" diameter. The M1029 is still considered to be potentially lethal under 10 meters and ineffective at distances over 30 meters.

The M1006 launches a solid foam "sponge grenade" at high enough velocity to wind someone or in extreme cases perhaps even break bones. The use of a softer foam sponge in the M1006 is likely a product of the serious injuries and fatalities caused by rubber and plastic batons in use by police forces around the world over the last 30 years or so. Despite this, the M1006 is still potentially lethal when fired at distances under 10 meters, having an 81 meter per second muzzle velocity, as well as, being largely ineffective at distances over 50 meters.