Upgrades for Reliability

[Scorpion8]

So, what's next?

Does your gun have the old-style, pre-flex-tab action?

Is there a description of this? Being an 870-newbie, I'm not sure what I am looking for.

[Synchronizor]

Here are some comparison pictures. Click for a larger version. I don't have an old/new image for the fore-end tube assembly, but the differences are all in the action bars. If you have an old-style slide assembly, then you must have an old-style fore-end tube assembly as well, otherwise the gun wouldn't go together.

[Scorpion8]

I appear to have the "old" style.

[Synchronizor]

Yeah, that's definitely an old-style slide assembly. With your gun being a 1970s model, the other parts are probably pre-flex-tab as well. If you want the most reliability - especially if you might need to reload or top-off your gun under stress - these really should be updated.

Like I said, you can mix old & new action parts, and each new part you add will improve things. The only exception is that if you get a new-style fore-end tube assembly, you need a new-style slide assembly to go with it. Otherwise, you can keep an eye out for sales or good prices on the used market, and update one thing at a time. Ideally you'd want all four eventually (breech bolt, carrier, slide assembly, and fore-end tube assembly), but a new-style bolt, carrier, & slide assembly with an old-style fore-end tube assembly is pretty reliable too. There's just a bit less support between the slide assembly & action bars, and the action won't run quite as smooth since the angles that move the shell latches are more abrupt on the old-style action bars.

[Scorpion8]

I went ahead and ordered the slide plate assy off MidwayUSA when I ordered the Mossberg choke tubes (see that other thread). The geometry is just a bit different, but as stated it should help. Its from the Marine Magnum, so it should have improved chrome.

[efriedrich]

I just did the extractor upgrade and it was quite simple, cant wait to try it. The wimpy mim extractor on the right already looks worn after only a few hundred rounds. The picture does not really do justice to the new extractor, its seems like a much beefier part.

[alpha15]

Jd mcquire sells the flex tab conversion kits on his website.

Here it is
https://tacticalgunsling.com/products/f ... ington-870

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