This cartridge is fired from 40mm Grenade Launchers M75 and M129 and 40mm Machine Gun Mk19 Mod 1 and Mod 3. The cartridge
is designed only for practice or for proof testing weapons.
This cartridge is a fixed round of ammunition. It consists of a one-piece solid inert aluminum projectile body together with a metal rotating band which is press-fitted into an aluminum bichambered cartridge case assembly. The case contains the propelling charge and percussion primer.
The propelling charge is contained in a spherical high-pressure propellant chamber with vent holes in the top. The chamber is sealed at the bottom with an aluminum base plug which is crimped to the base of the cartridge case. The hollow upper chamber in the case acts as a low- pressure chamber. A percussion primer is crimped into the center of the case closing plug.
No information about hazardous components.