Allis-Chalmers M50 Ontos “The Thing”
What happens when the Marine Corps decides it wants to show how much it’s compensating for something? The M50 Ontos, that’s what. Armed with six 106mm M40 recoilless rifles and one .30 caliber machine gun. Designed in 1952, it entered service in 1956 with the Marine Corps, with 297 built.
Problems with the design included the need for soldiers to exit the vehicle to reload the M40 recoilless rifles (exposing them to enemy fire), a small ammunition load, and massive blast-back if all six recoilless rifles were fired simultaneously. While designed as an anti-tank vehicle, the Ontos (Greek for “thing”) instead was used primarily for direct fire support, often in static defense positions. Marines loved it, enemy troops were terrified of it.
Ontos units were deactivated in 1969, with the vehicles returned to the United States and mostly cut up for scrap in 1970.
An exhausted crewman takes advantage of a lull in the fighting to nap on the hood of his Ontos anti-tank vehicle.
Frontal view of the M50 Ontos and its 2 Marine Crew during Operation Franklin. The Ontos is accompanying 1st and 2d Battalion, 7th Marines in the Quang Ngai Province in June of 1966.
