Everything you wanted to know about Garand rebuilds
The always knowledgeable Bruce Canfield has a great piece over at American Rifleman on field and arsenal care of the M1 while in U.S. service to help better illustrate just what happened to these guns.
When M1 rifles were received by an ordnance facility for overhaul, they were unpacked, serial numbers recorded and the arms were degreased as necessary. They were broken down into the major groups; stock group, barrel group and trigger group. The metal parts, except the barrel, were removed and set aside for inspection and gauging. The wooden components were inspected and repaired, refinished, or discarded as necessary. Barrels and receivers were inspected and gauged to make sure they were within “specs.” Any barrels that proved unusable–due to substantial pitting, wear or excessive throat erosion–were removed from their receivers and scrapped. Receivers passing inspection were refinished (reparkerized) as required. The other metal components were inspected and gauged. Parts passing inspection were placed in storage bins for subsequent use. Superseded (obsolete) components were replaced, and those that required modification for continued use were altered as necessary.