Lego minifig compatible Custom BrickArms M79 Grenade Launcher. The M79 grenade launcher is a single-shot, shoulder-fired, break-action grenade launcher that fires a 40×46mm grenade. It first appeared during the Vietnam War. It has earned the nicknames of "Thumper", "Thump-Gun", "Bloop Tube", "Big Ed", "Elephant Gun," and "Blooper" among American soldiers as well as "Can Cannon" in reference to the grenade size; Australian units referred to it as the "Wombat Gun"^. The M79 can fire a wide variety of 40 mm rounds, including explosive, anti-personnel, smoke, buckshot, flechette and illumination. While largely replaced by the M203, the M79 has remained in service in many units worldwide in niche roles.