1 piece vs. 2 piece magazine extension

[Reaper]

I am looking for a +2 magazine extension for my latest 870 project. Are the 2 piece extensions as sturdy as the 1 piece in a +2 extension? An example would be SAGE International vs. Wilson Combat. Are the clamps necessary on the 2 piece short +2 models?

[Chief Brody]

My 870P has the oem Remington 2-shot extension. The barrel clamp's screw goes through the groove in the extension, so when the extension tube loosens after a while, it can't go anywhere. I'm pretty happy with this setup.

It is my understanding that the clamp really is necessary for any extension (except a +1). Doesn't matter how tough and well made that extension is - without a clamp, it's still vulnerable to breaking off and screwing up the threads on the mag tube.

[Synchronizor]

The big advantages with two-piece kits are that they allow for a modular extension system with a common coupling that makes it easier and and less expensive to add configurations or remedy damage, and that (if installed properly) they ensure a tight and seamless interior transition between the magazine and extension tubes that is unaffected by variations in barrel guide ring placement, magazine tube length, or the presence of aftermarket accessories between the coupling and guide ring (so long as they're not overly thick). Also, in the event of a feed hang-up at the joint, the extension tube of a 2-piece extension can be loosened in the coupling to free up the snag without affecting the assembly or function of the rest of the gun. If the situation calls for it, a loose extension tube will usually stay together and feed for at least a few magazine's worth of shots. Freeing up a snag with a single-piece extension can be faster (if there's no clamp in the way), but the barrel will be loose and the gun inoperable until the extension is secured again.

In my opinion, the two-piece extensions don't have any major, fundamental durability advantages over the single-piece extensions. Extensions are stronger if they're clamped to the barrel, and you could say two-piece extensions come out ahead because they require a clamp to keep the extension tube from backing out of the coupling anyway, but there's nothing stopping you from using a clamp on a single-piece extension if you want the reinforcement. I suppose that in the case of an especially violent hit, a 2-piece design may transfer less stress to the base magazine tube than a single-piece extension simply because there are more more degrees of freedom in the joint, but that's kind of splitting hairs, and it's hard to make a blanket statement there when other things like quality, construction, and materials make a lot more of a difference.

If you want simplicity, go with a single-piece. If you want versatility, go with the two-piece. If durability is a concern, buy a quality steel extension and clamp it to the barrel, and you should be good either way.

[Reaper]

I ended up buying an ATI one piece aluminum +2 extension with spring. Found it at a hole in the wall gun shop in a town that I had taken my wife to for a specialist visit. Got an awesome deal on it too! This extension is going on a 870 that is NOT my primary HD weapon. Seems very well made of heavy gauge aluminum and carries a lifetime warranty.