No jams, Nova. Heaven only knows how many rounds I've fired from the 870, including abused and neglected Correctional weapons.
Ben, what you're describing is the clearance drill for when a shell is not pushed into the mag far enough and it comes back behind the carrier. Pushing the shell in until it "Clicks" means the shellcatcher is, uh, catching it.
Once just for my own information, I used a range day to test out some equipment back when I instructed. Ammo was 00 rotated from the towers, some shells had been pumped in and out so many times the rims were bent.Other rounds were telescoped from compression in the mag, or leaking buffer material, or otherwise not fit for service.I selected the most pitiful, roached out 870 in the armory, checked the bbl for spiderwebs, and headed out.
During the classroom phase of inservice training, I let a Sgt give the segment and took the stuff out to the line. I loaded up 4 of the ragged rounds and noted the dry squeal when the first was chambered. Using a tombstone target at 25 yards, I ran the 4 rounds as fast as possible. I "Combat" loaded the 5th through the ejection port and fired that off, duplicating our qualifier. I did it again until I ran out of junker rounds. The 870 squealed each time, it was that dry and unlubed. I racked it hard( The way it was meant to) and all rounds functioned.
I then placed a few drops of CLP on each action bar, racked it a couple times, and used up a couple light AA loads to see what happened. The squeal stopped,still no glitches.
I know nothing about the Nova, but the 870s' ability to work despite bad maintenance, bad weather, or bad training is well nigh supernatural...