In the last 20 years, I have built, rebuilt, or otherwise serviced and test-fired somewhere around 750 AR-15 and LFAR rifles and uppers.

I have seen bent barrels, as indicated on the exterior of the barrel.

I have seen drifting bores which effectively equated to a bent bore, confirmed with dip rod.

I have seen barrels loose in the upper extension which shifted with recoil.

I have seen poor stress-relief which walked when the barrel warmed up, and back as it cooled.

I have seen ~750 barrels which could be bedded, thermally interfered, lapped, or shimmed and properly torqued to deliver reliable and repeatable accuracy on target, most of which delivering less than 1.5moa.

I have never seen a semiautomatic AR barrel shot hot enough to irreversibly warp the barrel.