The background on this is that this 870P belonged to my job and was a range gun. It would give guys problems with locking up and being near impossible to work the action after firing. It only did this occasionally and since we try our best to "train like we fight" and all, when it happened no thorough examination of the failure was usually done at that time, just the instructor doing whatever it took to get the empty shell out. For the most part, for better or worse, when something goes wrong with equipment the assumption is that its the shooter until it happens to a known good shooter and a lot of the time these things are happening on a range, in the dark with four other guys on the line trying to qualify.

Long story short, eventually it happened to a known good shooter and they found a broken ejector (ejector rail, I believe, definitely not just the spring). The shotgun went back to Remington and the ejector was replaced but it seems like that was just a symptom of the real problem. In talking to one of the firearms instructors he told me that they were still having a problem with the gun locking up after it had been fired and that since it was about time to replace the range shotguns anyway he would be taking it out of service. When we take guns out of service they are sold to a distributor and when I heard what the distributor was paying, for all my shit talking about 870s not being that great based largely on seeing problems with this very gun, I couldn't help but make an offer of my own. So now I have it, and I'm working on making it the gun it should be. Why wouldn't I want to take on this headache, right?

Range time around here is limited and expensive so I'm trying to address any obvious issues before I take it out since I know that there is a problem.

Since the locking up problem only ever occurs after it's been fired and never with dummy rounds or unspent shells, I was thinking it might be the common rough chamber. In searching around this definitely seems to be more of an Express problem and this is a P. Also, I felt the chamber as much as I could with my fingers and it actually felt pretty smooth, even compared to my Wingmaster that is at least 40 years old. Further, the only thing this shotgun has ever been fed are Remington Managed Recoil Slugs and Buckshot and, briefly Federal Flight Control Buckshot. ("Train as you fight" and all) None of the poorly regarded cheap Winchester rounds. Never the less, since there was really nothing to lose I did the bore brush/steel wool polishing job on it and now it feels really smooth.

While doing that and checking over other parts I discovered what seems like an odd condition on the locking block and now I'm wondering if this could be the culprit. It is kind of flattened on the back edge of the part that locks into the barrel extension. Since it's part of the locking mechanism, I also want to confirm that the gun is safe before I try to find out if my chamber polish worked. Does this look okay?





So, 870 experts, could this be the issue?