870 Magnum Express Lock Up

**ThunderingWind** · June 22nd, 2008, 03:53 PM

I just bought a used 870 Express from my very reputable, local gun shop.

After 100 rounds on trap range, it started to lock up when I went to pump the action and eject the spent shell.

I put the firearm on SAFE and tried the action again. It would only "unlock" after a few attempts and only in the FIRE mode.

When I take it apart later tonight, is there anything for which I should be on the look out? What part may be worn beyond reasonable use?

**Lycanthrope** · June 22nd, 2008, 06:02 PM

Some of those are REALLY tight and need the throat polished up.

Were you using steel based trap loads by any chance?

**ThunderingWind** · June 22nd, 2008, 07:16 PM

Originally Posted by Lycanthrope

Some of those are REALLY tight and need the throat polished up.

Were you using steel based trap loads by any chance?

Thank you for your reply.

As a matter of fact, I was using Estate brand shells. They were a good deal.
Maybe they were "too good."

But it feels as if the lockup is father back in the receiver or where the locking block or slide assembly are.

**Lycanthrope** · June 22nd, 2008, 08:08 PM

Get a snap cap and dry fire her. If you can't replicate it with those, then I wager it's the throat needing polished up with some 2000 grit paper.

Steel cases swell and don't quite shrink back as much as brass based shells, so they may be more prone to sticking.

**WVBob** · July 3rd, 2008, 08:29 AM

Because it's new, you may have a little bit of the foam packing some place in it. I had my trigger lockup on a new 870 and when I took it apart it had a little bead of the foam packing locking it up. Take it down and give it a good cleaning and see if it helps.

**Tomcat088** · July 3rd, 2008, 01:12 PM

When I got my newest 870 Express, I had it lock up and not want to extract a few times after being fired. I've never had the older ones do that, but I've heard lots of people have this problem on the newer 870 Expresses. After I got about a thousand or so down it, it hasn't had the problem, so it did just need some polishing. Best of luck to ya.

**huntingbeaver** · July 3rd, 2008, 02:17 PM

870 express models are reknown for this -- not an issue with wingmasters. I sent mine back to the factory, and it still did it. Go to shotgunworld.com, do a search and you'll find remedies. I actually took a cleaning brush, wrapped it in steel wool, and stuck it in a drill -- after a few times of this, and bunches of ammo - it doesn't do it anymore.

**ThunderingWind** · July 3rd, 2008, 08:13 PM

Thank you for all the replies. While it is a used 870, it did not have that many rounds through it and the owner did not like the feel of the 3" shells.

So I got a good deal on a firearm that I can use with 2 3/4" shells for trap or swap barrels/chokes for turkey or deer.

I will work trhough the steel base ammo I do have as it was a good deal. I use it to help the kids get a feel for the firearm as they work the NRA Shotgun patch program.