Rifle, Self Propelled, Full Tracked, Multiple 106mm M50 and M50A1
The Ontos is a lightly-armored, tracked antitank vehicle carrying six 106mm recoilless rifles. Its full nomenclature is "Rifle, Self Propelled, Full Tracked, Multiple 106mm M50 and M50A1." Both the M-50 and M-50A1 variants were produced for the U.S. Marine Corps.
Ontos was used very effectively in Vietnam. During the March 1965 Battle of Hue, part of the Tet Offensive, the USMC Ontos provided direct fire to suppress enemy positions and to blow holes in the buildings so the Marines could advance. They were also extremely useful for providing suppressive fire and as counter-sniper weapons. In Lebanon the Ontos played the same role.
Ontos was disliked by its crews because they had to load and fire the recoilless rifles from an exterior, exposed position. The massive backblast also made it easy for enemy gunners to locate the Ontos.
M-50 Ontos manuals:
- TM 9-7222 Technical Manual, June 1957
- TM 9-2350-212-12 Operator's and Organizational Maintenance Manual, December 1959
- TM 9-2350-212-35 Ordnance Field and Depot Maintenance, September 1958
M-50 Ontos.
Ontos on Chu Lai beach, Vietnam, 1 June 1965. Photo taken shortly after descending from landing craft aboard the USS Thomaston (LSD 28).
USMC M-50 Ontos. One 106mm round is on the front slope.
