Been at this for awhile and I should know better. Every manual I have on my bench recommends taking a piece of wire and placing a bend on the end, sharpening it, and running it up an down inside the case to check for thin spots. http://bulletin.accurateshooter.com/...spot-problems/
I did not. "Once" fired brass bought off unfamiliar source. Looked great in the bag. Primer seating wasn't real tight but nothing I haven't used before. Visions of tight groups danced in my head. However pressure can be a stern master.

Shoving a 45 brass brush up the inside of the stuck case removed it. After removal I saw a spot that appears to of been over heated at some point. Was not readily visible on initial inspection.
Pulled remaining cases. Sure shortened my range time today.