Marine Corps · MOS history

0491 Title not stated in source

MOS 0491 was converted to MOS 0451 for Marines in the grades of gunnery sergeant through master gunnery sergeant.

The directory also lists 0491 Logistics/ Mobility Chief. Current service use is not established for this directory entry.

Search legacy codes Browse Marine Corps specialties

Codes named in this history

Listed in today's directory

These codes have directory pages; their current use has not been reviewed, so no current claim is made here.

0451Airborne and Air Delivery Specialist

Documented history

Title not stated in source

MARADMIN 446/03, published September 24, 2003, reported that the conversion was already complete. The original effective date is not stated.

The source does not state the occupational title for MOS 0491.

Source extraction notes

The cited source prints the MOS code but not its occupational title; no title was inferred. GySgt-MGySgt; source says conversion changes had already been completed, so original effective date is unresolved. The message says this conversion was already completed but gives no original date; year-only precision is retained.

Source documents (1)

Reviewed September 23, 2026 against references 1 and 2.

MARADMIN 446/03, FY04 Military Occupational Specialty Conversions
1. MARADMIN 446/03, para 2 table · source dated September 24, 2003 · cited by the explanation
Open source document (opens in a new tab)
2.MARADMIN 446/03, FY04 Military Occupational Specialty Conversions · event transcription · docs/legacy-data/usmc-mos-conversions.jsonl:185; MARADMIN 446/03, para 2 table · cited by the explanation
Open source document (opens in a new tab)

Historical information is drawn from the sources linked above. Classification dates are not personal service dates. Spot an error? Let us know.