My first thought is that you are experiencing excessive pressure. I would load down a few rounds and try them out. Next, inspect the chamber for rough milling or gouging or other damage. Clean your chamber AND brass too.
Years ago I had a 7x57 that would have the brass quite stuck in the chamber after firing. Thinking that it was over pressured, I loaded some VERY mild loads and got the same result. Stuck cases. I tried everything to no avail. Finally at wits end I noticed that the chamber walls had no shine to them but a dull matte finish. It was a very fine a very fine skim of rust from high humidity in the basement. I took a small wooden dowel, split the end with a hack saw and loaded the split with extra fine steel wool and lots of light oil. Chucked it in a drill and gave that chamber a good polish. Problem solved. Years later I saw the same in another rifle. The rust would hold the fired brass with an iron grip.
Years ago I had a 7x57 that would have the brass quite stuck in the chamber after firing. Thinking that it was over pressured, I loaded some VERY mild loads and got the same result. Stuck cases. I tried everything to no avail. Finally at wits end I noticed that the chamber walls had no shine to them but a dull matte finish. It was a very fine a very fine skim of rust from high humidity in the basement. I took a small wooden dowel, split the end with a hack saw and loaded the split with extra fine steel wool and lots of light oil. Chucked it in a drill and gave that chamber a good polish. Problem solved. Years later I saw the same in another rifle. The rust would hold the fired brass with an iron grip.
That’s super interesting. I’ll check that out because it never used to do this nearly as much as it does now. I’ll update with results




























