AR frozen in battery

[oldmann1967]

Just like driving a vintage Detroit Diesel. Slam your hand in the door first.

[10x25mm]

There is a decent probability that this seizure was caused by one or more sheared bolt lugs. This has been a common problem on big bore AR-15s, even with low round counts.

If it is just one lug which sheared (usually the one next to the extractor), the bolt carrier should move back and forth the length of the bolt cam pin dwell. But if several lugs sheared, the bolt carrier will likely not move at all. They typically freeze because the bolt body torques off axis.