I will say that while not normally a problem the pumps don’t have the extraction camming power of a bolt rifle. The second buck I ever killed I had to give my 760 a Pogo stick whack on the butt while holding the forend to get it to spit the empty out after the first shot. Likely due to a dirty chamber back before I knew any better.
I've seen a couple rifles (one 760 included) that had a very fine covering of rust in the chamber that would hold spent shells like a vice grip, even with very light loads.
Very fine steel wool on a slotted dowel with lots of light oil chucked in a slow drill fixed them both.
Yep, a lot of them with a lot of people had the habit of getting used hard and not well cared for until all of a sudden there's a problem. Guy dropped one off here because it wouldn't go off. Said the trigger would pull and nothing would happen. Took one look in the chamber and seen the problem. Dirty, rusty. Action would go closed but too tight to go forward enough to completely close where it would lock the action bar, so therefore the trigger wouldn't set.
I cleaned it by hand with a slotted dowel and fine scotch brite soaked in Hoppe's. Shined the bore right up. Worked like a top after that .
