How do I mount a Magpul UBR on a Sig556 Swat Classic folder?

[SoCal Gunner]

I have a Sig 556 Swat Classic - The one with the quadrail and folding stock. The quadrail makes the front end heavy and the cheap feeling plastic adjustable/folding stock (pinned anyway, thanks Kali) does nothing to offset the weight.

I see people recommending a Magpul UBR to balance things out, but how do you actually do it? I know there are adapters out there: http://www.shop.doublediamondsupply....SIGADTM401.htm AND https://www.cogunsales.com/index.php...uct-flyer.html.

I'm not sure how everything is going to mate up when trying to fix it to that adapter, rather than a a receiver with buffer retaining pin and a stock plate with retaining pin, etc.

Here is a youtube vid of a Magpul UBR install on an AR receiver: http://www.youtube.com/watch?v=2gD5b...eature=related

[sd1023x]

There is nothing inside the stock tube for a Sig 556 no springs, no buffer. The Magpul UBR looks to have its own tube so basically all you need to do is screw it on DD Supply stock adapter and mount that stock adapter to your sig 556. Its fairly simple.

Hope this helps

[tiger222]

Sent you a pm - if you want to swap lowers lmk I have the earlier AR buttstock lower - the ubr just fits right on - no adaptor needed.

[slick_711]

Yeah, find someone to swap lowers with...

[rareair]

I bought & installed one of the Double Diamond adapters onto my SIG 556 SWAT. Simple and straight forward conversion. I'm using a ACS stock, but it's the same procedure for the UBR

[SoCal Gunner]

Thanks for the replies guys, PMs answered and PMs sent.

[rareair]

Do you already have the MagPul UBR in your possession? It has a different mounting configuration when compared to regular stocks. You must thread the buffer tube assembly into the back of the DD adapter. Once it gets close, to align the pin there is a flat head screw at the rear of the buffer tube that will allow you to take up the remaining slack. I have an extra UBR stock so I went ahead and mounted it to my SIG so you can get a visual of what you want to accomplish.



Im kind of an accessory whore, so my UBR also has the strike plate attached

[SoCal Gunner]

Thank you for the reply - I love this place - Pictures and all! Sounds pretty simple and straight forward, perhaps I was misled or just misunderstood another forum members issues.

Any additional thoughts or comments while you have the UBR on there? Any reason you prefer ACS over the UBR since you own both?

[rareair]

Any additional thoughts or comments while you have the UBR on there? Any reason you prefer ACS over the UBR since you own both?

If I was in a State where a folding stock wouldn't be a problem, I'd run the UBR due to it's cheek rest design. Being flat, the folding feature would be great.

The ACS has a much more ergonomic feel when in a natural shooting position. But because of the battery compartments on each side, the folding feature would be hindered due to the shape. And since I'm in California, and the folding feature is outlawed to civilians, I run the ACS.

[rareair]

I have a Sig 556 Swat Classic - The one with the quadrail and folding stock. The quadrail makes the front end heavy and the cheap feeling plastic adjustable/folding stock (pinned anyway, thanks Kali) does nothing to offset the weight.

The OEM SIG stock is a nice piece. Being hollow, I wonder if it'd be possible to insert some lead weights into it to achieve the desired effect of balancing the font heavy rifle? With a heavier butt stock, it can also help reduce felt recoil

[21SF]

Im kind of an accessory whore, so my UBR also has the strike plate attached

Yes, Yes, you are. Lol

Judging by the pics

[mqd123]

Do you already have the MagPul UBR in your possession? It has a different mounting configuration when compared to regular stocks. You must thread the buffer tube assembly into the back of the DD adapter. Once it gets close, to align the pin there is a flat head screw at the rear of the buffer tube that will allow you to take up the remaining slack. I have an extra UBR stock so I went ahead and mounted it to my SIG so you can get a visual of what you want to accomplish.



Im kind of an accessory whore, so my UBR also has the strike plate attached

Wow! Where did you get that strike plate? That's pretty cool, never even thought of that.

[rareair]

Wow! Where did you get that strike plate? That's pretty cool, never even thought of that.

I'd like to tell you I invented it, but I can't. MagPul offers the strike plate as an optional accessory

http://store.magpul.com/product/MAG331/34

[rareair]

Im kind of an accessory whore, so my UBR also has the strike plate attached

Yes, Yes, you are. Lol

Judging by the pics

Have you seen my other rifles?

[SoCal Gunner]

Sent you a pm - if you want to swap lowers lmk I have the earlier AR buttstock lower - the ubr just fits right on - no adaptor needed.

Thought of you when I came across this: http://www.amazon.com/UTG-Model-Fold.../dp/B002TUSDQ2