Dang I wish I had read this thread before I put so many 5.56 rounds through my PSA and DPMS over the years. Now I just know there will be problems. I expect both of my rifles to fail miserably any time now.
Part of being an AR owner is that you must maintain and work on them occasionally. One of mine has over 900 rounds without a complete cleaning, I just swab the barrel and chamber and oil the bolt carrier every 2 range session. This is a test for the rifle upper only, the lower is swapped between 3 uppers.
I’m no expert but I have fixed more than a few problems that have occurred over the years.
Army rifle training stuck in my brain but can’t recite my general orders anymore.