I think, maybe, somewhere north of 4500 rounds or so to shoot it out? IDK, we just shot it a bunch and didn't track it. However, a significant part of that was shot hot and fast, which is not good for a carbon steel (or any for that matter) barrel. When my daughter is in the shooting mood, I let her shoot. Much of that was shot in in the summer when the heat is bad. That is another reason I went with a factory takeoff to put back on it. It will be abused the second time around too, I am pretty certain. It still shoots fairly well, all things considered. I am really ready to step up the twist though to get her into a heavier bullet. Otherwise we could get a couple more years out of it.
I am not really a hot rodder when it comes to loads. I run it up somewhere around a generally accepted maximum, wherever it shoots good or really wants to shoot, and call it good.