Machinist's Mate · Merged into SPCM, effective 1964
Malin/BUPERS source assertion: Established 1964; combination of BT and MM ratings at E-9. Normalized as merged/included. The source explicitly limits this combination to pay grade E-9; it does not assert that lower-pay-grade use of the predecessor rating ended.
Sources
- Charles A. Malin/Bureau of Naval Personnel, Compilation of Enlisted Ratings and Apprenticeships, U.S. Navy, 1775 to 1969 (rev. Dec. 1969) (#anchorm, Master Chief Steam Propulsionman (SP) entry; reproduced on archived Ohio PDF p. 10)
- Charles A. Malin/Bureau of Naval Personnel, Abbreviations Used for Navy Enlisted Ratings (1970) (alphabetic abbreviation list, MM, SPCM entries)