I don't know, to be honest. I bought a custom ar from the original owner, but decided to go a different route instead so I disasembeled the rifle for parts, kept that I needed and put the rest for sale. I didnt shoot it at all, but I have no idea how many rounds original owner fired. It got some fouling, so it was through at least one good range session, but nothing is worn and rifiling is like new.
Thanks for your question.