Ontos Crewman
The MOS creation and retirement dates are also undocumented in these sources.
Marine Corps · MOS history
0353 Ontos Crewman
A direct successor to MOS 0353 has not been established from the cited sources.
Overview
Historical Marine Corps specialty for crewmen of the Ontos antitank vehicle, which also provided direct fire support in Vietnam.
Codes named in this history
No successor relationship has been verified for this record.
Documented history
Sources and limitations
- The personnel manual's 0341 example describes a mortarman qualifying as an Ontos crewman and the ordering of primary and additional MOSs. It does not establish 0341 as the successor to 0353.
Source notes
0353 was the historical Marine Corps specialty for an Ontos Crewman. The M50A1 Ontos carried six M40 106 mm recoilless rifles. Designed as an antitank vehicle, it was also used for direct fire support of ground units in Vietnam. The Marine Corps Personnel Manual explicitly names MOS 0353 in an example of a Mortar Man (0341) qualifying as an Ontos crewman. After qualification, the Marine could hold either 0353/0341/none or 0341/0353/none as the primary and additional MOS sequence. This is a qualification example, not evidence that 0341 replaced 0353. The cited sources do not establish the MOS creation date, retirement date, or a direct successor, so those remain unknown.
Source documents (2)
Reviewed October 1, 2026 against references 1 and 2.
- Marine Corps Personnel Manual, Chapter 3, Classification of Military Personnel
Location: Paragraph 3102.4, printed p. 3-12 (PDF p. 10), qualification example naming Ontos Crewman, MOS 0353
Used in the reviewed explanation.
- National Museum of the Marine Corps, Marine Corps Vietnam Gallery Weapons
Location: PDF p. 1, M50A1 Ontos entry
Used in the reviewed explanation.
Historical information is drawn from the sources linked above. Classification dates are not personal service dates. Spot an error? Let us know.