Recoilless rifle
"SKZ" redirects here. For the inscription, see Shapur I's inscription at the Ka'ba-ye Zartosht. An M40 recoilless rifle on its M79 "wheelbarrow" tripod. Diagram of the operation of a recoilless rifle using a vented case. A recoilless rifle , recoilless launcher or recoilless gun , sometimes abbreviated "RR" or "RCL" (for ReCoilLess) [1] is a type of lightweight artillery system or man-portable launcher that is designed to eject some form of countermass such as propellant gas from the rear of the weapon at the moment of firing, creating forward thrust that counteracts most of the weapon's recoil. This allows for the elimination of much of the heavy and bulky recoil-counteracting equipment of a conventional cannon as well as a thinner-walled barrel, and thus the launch of a relatively large projectile from a platform that would not be capable of handling the weight or recoil of a conventional gun of the same size. Technica...