Rem 870
 

First Hello to everyone I am new here .

I have the 870 express 12 gage with the rifled cantilever barrel.
I purchased to make it my slug gun for deer and it is 5 years old or so.
My question has to do with the pump action or slide if your will. It seams to cycle shells just fine when loading or unloading when holding the little lever in by the trigger. Now when making a shot I do not grab the forearm , it pretty much rest in my hand. The kick from the shot will open the breach about a inch or so. Now when I pump it to eject the shell and load another it seams harder to pull forearm back then it should be. Just like it's having a hard time kicking the spent shell. It has the 3 inch chamber but I am not shooting the 3 inch loads. With this I ruled out oversize shell case.
Thinking it has to be in slide or kick pin or the shell extractor on the bolt. Any Ideas I would be Thankful for .

I have heard that some Express models have rough chambers. Honing the chamber lightly may help this situation.

Well for starters I wanna be sure you're not talking about the tension you get from cocking the hammer back after it's been fired. Dry-fire it and pump it to see if that's where the problem might be. Since the chamber opens up from recoil that much, it seems unlikely that a rough chamber would explain your symptoms. A rough chamber is common in 870s and can create the need to slam the forend back to break the shell loose. That can be more or less solved by honing the chamber. However the bolt doesn't usually open up much when that happens; and you say it moves fine when it's already cocked which makes me think your problem is elsewhere.

The Model 1200 Winchester that I bought in 1967, but that hasn't had that many shells though it, is just as you described your 870. It has a 2 3/4" chamber and when I shoot turkey loads in it and have a light grip on the forearm the heavier recoil will partially eject the spent shell and then when I go to jack it on open by hand it is fairly stiff just like I think you are talking about in your 870. When loading/unloading unfired shells while keeping the button on the trigger guard depressed it is as smooth as silk. I think we are experiencing the same thing and my theory is it's just that the spent shell has expanded just enough to cause a slight hangup when it is not completely ejected all in one movement and it makes me doubt there is a thing wrong with either gun. It's just something I have noticed every time I shoot it infrequently with those turkey loads each Spring because that have more poop to them than regular shells that don't cause the action to start opening on it's own. Anyway, that's my theory and I don't plan on doing anything to the gun.