here's answers to yours that might help me:
-Brass was previously fired from this gun
-COL was within range
-all other rounds have been checked for fit after this and all are good.
-My son chambered the round in his handi-rifle and he said it closed rough. That prompted him to open the rifle and check the round.
- I attempted to fire the round after it was stuck ( not wise in afterthought )
- We waited 1/2 hr after round was discharged before forcing in out.