Digging in the wood pile again.

[Bob Seijas]

A is "Amola," a steel alloy developed by Chrysler, and CM is Winchester Chrome Molybdenum steel. GCA solved this old WRA mystery when Tony Pucci speculated it was chrome moly and sent some CM parts for chem lab testing that confirmed it. Bruce Canfield later re-confirmed it from the Pugsley papers he acquired and also a memo from T. Boak authorizing its use.

GCA members have solved most of the mysteries of Garand collecting and the GCA Journal has published them. If you're not a member you should be, it's $25 well spent. Just sayin.