Was into MG shoots between '86 and '12. Early on was given advice to buy only Colt stuff (reread the timeline). Indeed, the only problems I had were related to beat up Orlite feed lips. Those without cracked lips ran as good as USGI no-finish remaining alloy mags.
Not one failure gun related. Unless you consider one extractor hook per 10k steel cased excessive (it isn't). Heck, I had more trouble with my Uzis. Learned about M16 lube requirements......pretty much exactly what Rogers said. Keep it wet and it works. We'd run 1k/day for few days - no cleaning. One of my 11.5s now has about 20k on it. Rifling is about gone first 3-4", but it did 4" for 5 at 100 yds this year with my General Dynamics M855.
At shoots hung out with rental guys who had 1-2 orders of magnitude more rounds on their guns. They stuck with Colt. Finally saw an action spring become too weak. It was shortened far below what spec calls for replacement.
This is not a criticism of those who are competent building their own. But far and away the worst guns/uppers were the builds. 90% of "issues" I saw over those years were with builds. BM, M1S, etc were overrepresented vs Colt with problems. But they were alot better than most of the builds. Poorly indexed/torqued barrels with feed ramps not indexed. Undergassed usually. Rarely overgassed with owners having zero clue about dropped extraction fixes.
Moving forward in time - have no experience with Anderson and Bear Creek. The worst ARs I've run across in recent years have been Sigs. Three different guns purchased by three different friends all failed to run even domestic .223 55s. All three called Sig and were told the "needs break-in" canard. Flame away, but I won't own an AR that won't run 100% on steel. None of the Sigs got sorted out to 100% reliable after 500 rds+ of M855-ish stuff. This was about 10-12 years ago, so possibly they've got this fixed.
Will say Smith and DPMS seem to make decent stuff. No experience with the pricey guns like Baer, DD, BCM, LW, etc.
