Ok I’ve been loading quite a while and loaded a new cartridge the other day. 7mmBR. resized some once fired factory brass and didn’t have the gun on hand to test fit. Proceeded to load ten rounds. Bolt is tightly snug on closing. Broke down ammo checked the trim and decided to re set the die and start all over. Did one case and still no bueno. Ok I don’t have a neck trimmer so I used a makeshift one on the single case. Again no bueno. Factory ammo works fine everything seems to mic within specs. Polished a case and gave that a try actually seems a bit better hmmmm. Made sure the port hole on die was clear and open. Cleaned die and tried another case. I have had this on a case of different calibers here and there before but just a trim or resize always cured it. Any advise??????