Mossberg 500 bolt loose

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May 19, 2011
South Dakota
Was out shooting my mossberg 500 earlier this week and took it apart pretty far to give it a good cleaning. I have never actually cleaned the action in the 5 or so years I've had it. Got a lot of pieces if weeds and dirt out if it. When I finally got it back together the bolt assembly is loose it will slide back and forth maybe a quarter of an inch which I know it never did before so I'm assuming I put it back together wrong. Also the it is kind of hard to work the action it isnt nice and smooth. Anybody know what I did wrong?
Field strip it again and put it back together again, and see if that fixes it. Sounds as if the bolt isn't back on the bolt slide correctly, or the bolt slide isn't installed on the action bars of the slide assembly correctly, Too hard to tell without seeing it, doesn't really matter if a quick field strip and reassembly will fix it. to ID parts by name or see for pictures

Good luck with it,

Mossberg 500's are one of those weapons that can be put back together such that they will "work" (or appear to) when in fact they aren't put back together properly. And it is easy to do, I still do on occassion. Do like Lee said, tear it back down, and then reassemble it. Don't force anything, and you may have to bend the extractors back if those got bent (if they don't work when you get it back together). A youtube video might be helpful if you have questions about it.
I took it down a couple times and put it back together and still the same thing. Ill try it again maybe it's just some stupid little thing I'm doing wrong lol. I originally used the stickied guide to take it down with no problems it's just the putting it back together part
Ok well I tried It yet again and it all seems to go together easier like it should be right but the bolt still slides. Followed several videos exactly and I seem to be doing it right. It only does it when the barrel is off with the barrel on it seems to work fine and cycles shells ok. However I don't remember it being lIke that with the barrel removed. Any one else's do this on the chance I don't remember how it worked? Lol I'll look at it tomorrow after I've gotten some sleep and see if I can figure anything else out.
When the barrel is off there's nothing to stop the bolt from going a little further forward than it does when the barrel is installed.

Sounds as if you've discovered a feature, not a bug... :D

Ha ha well sorry for pretty much wasting every ones time hadn't had it apart in years and couldn't remember how it was. Wanted to make sure it was right before I actually went out and shot it never remembered it doing that so I wasn't sure lol feel pretty stupid right now :D
Better to be careful and feel silly... the only dumb question is the one you don't ask.

I went through that with mine, did a complete reassembly, and it didn't do it any more. It's needed clearance for it to be taken apart and put back together, it is a required feature.
Until you get an 870, you'll just have to take it apart and keep trying to get the reassembly right. The bolt sets on top of a sort of plate that rides on the rails. I'm thinking you may have the plate facing the backwards.
I have one 500 and had the same reassembly issue as you are, but once I relaized the right way I did it several times so I would remember the correct way.
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