M203EXPIC 40MM Grenade Launcher (Picatinny Rail Mount System) The AirTronic USA M203 system, is a breech-loaded 40mm grenade launcher fully compable with any 1913 Picanny Rail. With a extended receiver to accommodate all rounds, to include Star Parachute Rounds. The M203’s lethality and broad versality make it the prime choice of the U.S. and Foreign Armed Forces as an essenal weapon in both offensive and defensive operaons. Stand-Alone conversion kits and mounng hardware for the AK-47 are available.