In nature, scorpions are deadly creatures that wield a fearsome sting. So, it makes sense that they’ve lent their name to many a weapon, like the F-89 Scorpion and the Textron Scorpion, just to name two of the most prominent. One of the lesser-known weapons to hold this arachnid moniker is the the M56 Scorpion.
The M56 was a contemporary of the M50 Ontos, an anti-tank six-shooter that served with the Marine Corps for 13 years, giving them a lightweight vehicle with a potent punch. The Army took a different approach in fielding a similar vehicle.
Instead of the six 106mm recoilless rifles the Marines selected for the Ontos, the Army opted for a single M54 90mm gun as the primary armament for the M56. The Scorpion had 29 rounds for the main gun — which was its only weapon.
The Scorpion was intended to give the 82nd and 101st Airborne Divisions some serious anti-tank firepower. They needed something lightweight — and the Scorpion was only 15,750 pounds, according to MilitaryFactory.com, less than a third of the weight of the M41 Walker Bulldog light tank. That weight combined with a 90mm gun and you’ve got yourself a winning vehicle, right?
This M56 at the American Armored Foundation Museum shows how small the M56 Scorpion was, despite its powerful 90mm M54 gun.
(Photo by Ryan Crierie)
Well, not quite. It turns out that when you’ve a powerful gun on a light vehicle, the recoil can be vicious. In this case, it was real bad – firing the Scorpion’s gun could send it flying three feet into the air. As you can imagine, this was an extremely uncomfortable experience for the crew in two ways. Not only did it jolt them about, risking serious injury, it also exposed their position to enemy forces — which is last thing you want on a battlefield.
The M56 Scorpion, like the M50 Ontos, saw action in Vietnam.
Unlike the Ontos, the Scorpion did see some export sales. The Spanish Marines bought some, and so did Morocco and South Korea. The M56 saw action in the Vietnam War, primarily serving with the 173rd Airborne Brigade. The M56 was eventually replaced by the M551 Sheridan, which not only saw action in Vietnam, but served into the 1990s.
Learn more about this lightweight Scorpion in the video below!