Hello all, I am new to milsurp rifles and decided, in my usual fashion, to jump in over my head. I recently purchased a barreled action for an Ishapore 2A1. It's essentially an Enfield No1 Mk3* chambered in 7.62x51, with a few minor differences (different butt socket design, different sights markings, different nose cap, and of course a different magazine). I had been working about corrosion mitigation since I got it, due to seemingly being stored dry for a couple of years. Nothing major. I was at the local range and happened to find a couple of .308 Winchester brass which I took home to test fit in the chamber just out of curiosity. It was then that I realized that it seems a previous owner had been using the wrong extractor (one for a No4 Mk1 modified to fit a 2A1) and in doing so damaged the extractor notch in the barrel. A small amount of metal is smashed out making the mouth of the chamber out of round. I will attempt to post a photo later so you can actually see what I mean. Anyway, my question is this: What would be the best way to fix this problem? I paid $70 with shipping for the barreled action, so I'm hoping to not have to rebarrel the gun. It would cost less to just buy another and actually look it over thoroughly before the return period is up. I was thinking about very gently and carefully filing away material until a fresh round chambers. The damage is at the back of the chamber where the brass of the case is thickest. I doubt one or two thousandths of an inch would matter that much. I am hoping you fine people can help, or at least tell me that I've got a stupid idea in my head.