M-11 Jr has decided he no longer wants/needs his SIG 556xi SWAT and is giving it to me. (Is he a great kid, or what?!) While the folding stock is nice, I'd rather have an adjustable folder. I know there are conversion kits, etc., but have no idea the best way or sources to accomplish this. So, I turn to the ultimate source- SIGforum!

I put a Magpul CTR on my 556. If memory serves it takes the commercial model. Commercial-spec buttstock tubes, in which the buttstock goes around to attach to the rifle, have a diameter of 1.168”, while the Mil-spec is slightly smaller and has a diameter of 1.148”. A buttstock designed for one size tube will not work on the other. So just measure your buffer tube and order the appropriate stock size. No further midis required.

You will need the M4 stock adapter, which recently sold out on the sig Sauer USA web store and at Numrich arms.

I have a 556 classic with the old US (non-swiss) style adjustable folder on it. Like this one here.

If they will swap (we will have to confirm the attachment points are the same) and you want to trade stocks, I would be game. My stock is in great shape, I just prefer the look of the fixed length options.

Sounds like plan to me. My son is coming up Wed to drop it off, then I have a 24hr wait time. (Thank you Chicago and associated Democrats0. I’ll get some pics and see where we stand. My email’s in my profile.

I just sent you an e-mail, so we can take the details of this off-forum. Let me know if you do not receive it.

quote:

Originally posted by Thingol:
I have a 556 classic with the old US (non-swiss) style adjustable folder on it. Like this one here.

If they will swap (we will have to confirm the attachment points are the same) and you want to trade stocks, I would be game. My stock is in great shape, I just prefer the look of the fixed length options.

The mounting points are the same on all the 55x guns ... I’ve put a gen2 or 3 on my 556 pistol when I SBR’d it and upgraded to a 556Xi when they came out as well.