I just had the same type of situation this last week. I had purchased a hundred rounds of empty belted brass from a fellow member. The brass looked great! Then when I started priming after sizing and trimming, I found extruded marks on the case heads. They were half round marks from a ejector hole in the bolt head. The primers almost fell in the pockets! Several ones I could seat primers with a fingertip! The seller has promised to return the sale price, and all went into the scrap bucket after having the case necks smashed with a hammer. I think these were proof loads that someone got ahold of, for they looked like they had to be around 80,000 psi to flow like that. It was a shame for the brass is an old caliber one and it is hard to find. The toolman.