US Cartridge, 40mm Practice, M385A1
This practice cartridge is fired from 40mm Grenade Launcher M75 and 40mm Grenade Machine Gun Mk 19 Mod 3. The cartridge is designed only for practice or for proof testing weapons. Not authorized for use in M129 Grenade Launcher.
This cartridge is a fixed round of ammunition. It differs from the M385 cartridge in that the ogive matches the shape of the M430 projectile ogive. 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. The case contains the propelling charge and percussion primer.
It is linked only with the M16A2 link, whereas the M385 is linked with either M16A1 or M16A2 links. 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.