One of the contract provisions for the M1911A1 pistols was a requirement that every part in every pistol be fully interchangeable with every other pistol, regardless of manufacturer (Colt, Remington Rand, Ithaca, Union Switch & Signal, Singer).
While on casual status between jump school and pathfinder school at Fort Benning, Georgia, in 1969 I was detailed to the post armory. We disassembled, cleaned, and reassembled many hundreds of various weapons used for range training by multiple units including pistols, rifles, and machineguns. The M1911A1's were detail-stripped, then all the barrels went into one box, all the slides into another box, all the frames into another box, all the firing pins/springs/retainers into another box, grips in another box, etc. After cleaning all the parts(boiling water and soap, followed by solvents and brushes, etc) the pistols were reassembled with random parts, as each were pulled from the various boxes. No thought was given to keeping original parts together, and not a lot of attention was given to overall condition on the pistols. This cycle was repeated constantly, as weapons went out to ranges for OCS, IOBC, and other Infantry School uses, then returned to the armory for cleaning and service (some with "trouble" tags attached for special attention by the post armorers). Seriously worn or damaged pieces were packed up for shipment to an Army Depot for the next level of maintenance or destruction.
Rifles and machineguns were gauged for throat erosion, muzzle erosion, and other symptoms of excessive wear. Out-of-spec parts were replaced with new parts. As I recall, only the M14's required attention to keeping the correct bolt with each rifle (to assure proper headspace). There were still racks filled with 03/A4 sniper rifles, M1 Garands, M2 Carbines, M3 SMG's, and M1 Thompson SMG's, .38 revolvers (Colt and S&W), 1897 and Model 12 Winchester "trench guns", although none of those were in general issue at the time.
In addition to all the various pistol manufacturers we worked on weapons made by Rock-Ola (jukebox manufacturer), General Motors Hydramatic Division (transmission manufacturer), TRW (satellites), High Standard, GM Guide Lamp, Rock Island Arsenal, General Electric, and other interesting sources.
A couple of years later I spent a few months with an Army Marksmanship Training Unit where I learned a lot about what makes the 1911's work best, shoot most consistently, etc. We had Service Pistol and Match Pistol categories, and some of the best pistolsmiths in the world at that time. Parts selection, based on manufacturing tolerances and gauged dimensions, was everything in the Service Pistol category, as no modifications were permitted. Barrels, barrel bushings, triggers, sears, safeties, all matched as closely as possible to the frames and slides (also carefully matched up). Cases and cases of new replacement parts from every source imaginable (Colt, S&W, H&R, Savage, Springfield Armory, and others, most dated 1940's but some as late as the 1960's).
Match-grade parts were stamped "NM" (barrels, frames, slides, bushings). Match pistols were produced on new Colt frames in the MTU shop, and pistols were constantly coming back through for examination and rebuilds.
I remember going to a pistol match while I was coming off the flu. When I turned in my score card to the NCOIC he looked at the card, stared at me and demanded to know what I had to say for myself. I told him I felt so bad I wanted to go out back and shoot myself. He told me to take two rounds.
Lots of old memories.
