Friend loaded a round backwards in my M1014 and shot... what now

I don't know how that round even got it, but he literally inserted a round backwards into the tube and caused a double feed...the range administer was able to poke both rounds out with a knife. I looked into the body and did find some chips & gashes inside the body & on the shell retainer. I don't expect any of you have experienced this, but I do want to get some advise on what parts should I inspect to ensure nothing is damaged?