Home Forums Hunting & Shooting AR and Tactical Rifles Sig Brace House Gun

Today I had the opportunity to handle a few different Sig Brace setups. After doing so, I can appreciate their appeal as a House gun.

If you were going to set one up for that purpose, what would it look like?

Uses it had a suppressor I wouldn't be interested.

Very nice.

So what did you go with, a 7 1/2 and a 10 1/2?

Which brake are you using?

The black one is a 10.5in 5.56 Colt with Surefire brake.

Tan one is an 8in Noveske 300 BlackOut with Surefire brake.





The real benefit is that they are legally pistols. With barrier blond loads= Truck guns extraordinaire.

You'll wanna go no shorter than 10.5in on a 5.56mm, 11.5in is better and pay heavy attention to bullets.... As always.

Those are pretty neat.

Yes, legally being a pistol makes a difference in Colorado as well. You can have one in the tube in a vehicle if it's a pistol, but not a rifle.

I see you are also running two different buffer tubes?

Just what was on hand.

The KAK extended SUPER SIG buffer tube is the way to go.

Are those ass heavy? The Sig braces?

Now I understand the utility of the 300 BO better. Thanks for posting those pictures! This would be a handy tool. I know SIG makes the full up guns in 5.56 and 308 winchester but not sure I trust them. I have to look into a 300 BO AR pistol with the SIG arm brace.

They are not.

Here's an example of someone using one....

Does the SIG arm brace rotate or slide on the KAK super sig buffer? What is the "ideal" barrel length for a 300 BO pistol. We can hunt deer with a center fire pistol in GA.

Not really. It's tight but a a piece of skateboard tape would cure any slippage.


The Barnes TTSX 110gr Blacktip bullet upsets completely at 300 yards from an 8 inch barrel. So an 8 inch Noveske or AAC.

Spend the $200 and SBR it!

heck, get two of them, one for each arm, and run screaming at any home invaders. You actually won't have to shoot them, they will out-run you to get away.

hell Pat with that 45-90 of yours you can just wait till a herd of them get lined up and take them all out with one shot

can you post a video of this technique! I am sure it will be an instant campfire classic.

Oh I could see it going viral. Not in a good way, however

I'll be skipping the tax stamp. Too much of a PITA to take it across state lines.

That is my take as well. Also final see the merit of the 300bo like a 11 inch barreled pistol and much more effective than a 45acp then there is the 30 rounds thing. I hate this place now I have to kill a deer with a 30 caliber pistol.

I kept wondering what the big deal was with people saying they'd get a pistol instead of an sbr. Now I understand, and I'm thinking I just might have to build one. Only thing is I'm not keen about the muzzle blast from a 10.5" tube and if I put a can on it I'm in the same boat as an sbr.

I kept wondering what the big deal was with people saying they'd get a pistol instead of an sbr. Now I understand, and I'm thinking I just might have to build one. Only thing is I'm not keen about the muzzle blast from a 10.5" tube and if I put a can on it I'm in the same boat as an sbr.

You're only in half the boat as an SBR.

SBR with a can = 2 stamps. And the suppressor can be moved from gun to gun, making it a little more useful than an SBR lower.

Yeah, I know it needs two stamps and the can will interchange between guns. It's the hassle, expense and wait on NFA items I'm grousing about.

If you buy a stripped lower marked "other" on the 4473 form by the dealer and put a short barrel on it....is it a pistol??

Taking a pistol across state lines is different from taking an SBR across state lines. I will live without a suppressor.

Wait someone already said that!

I don't think I can get an AR in rifle, handgun or SBR through Canada, so the NFA angle is mute on that end. However I could see myself putting a 22rf, 22cf, 30, 35 and 45 suppressor to use

Just to clarify.... You use them like a rifle...

More or less, yes. Keep in mind, I'm not an attorney, nor did I stay at a Holiday Inn Express last night.

If you set it up as a rifle, it's a rifle, and must remain as a rifle.

Set it up as a pistol, it's a pistol, and must remain as a pistol.

I asked an FFL about it this weekend and he said the label the stripped lowers as "receiver" on the form.

No kidding?

I have done more research on it, my FFL labels them as "other" when he sells them and once you build it as Pistol its a pistol forever.

the 12 inch barreled uppers are cheaper than the 9 inch uppers I have seen. I guess 9 is long enough and more popular as a pistol length i.e. better balance.

uber awesome.

No. Really. He's read some of the schidt you've posted, therefore he knew that needed to be stated:)

I looked at a Sig Pistol today with the brace. It looked like about an 11.5 in LOP with that particular buffer tube that Sig uses. The internet buzz says the extended KAK buffer tube is the one to get. It has a raised portion to prevent the brace from sliding forward. An 11.5in upper, gassed right, with the proper spring and buffer, would be a slick little setup. A good comp like a BCM would help. I'm thinking about doing one with an A1/carrying handle upper and putting an Aimpoint on one of the old SOPMOD gooseneck mounts.

On a side note, how are giys doing the same swaps with Encores and not running afoul?

Good question.
I wouldn't do it.

If it is first assembled as a pistol, it can be turned into a rifle, and swapped back. If it is first assembled as a rifle, it is a rifle and can not be switched into a pistol.

I looked at the SIG in 556 they have a pistol in 308 as well, there IS NO LIMIT to insanity. Can you imagine shooting a 12 or 13 inch 308 in your bedroom? Not sure about the SIG's they look nice but seems to me you could make something lighter, IIRC the SIG's were Piston guns. Damn this means I have to buy another aimpoint, I am going to be the most well equipped mall ninja in the poor house before long.

So why wouldn't that same formula follow suit with an AR pistol?

Does it have something to do with the ATF's classification of pistol that includes an OAL that does not exceed 26"?

Encore pistols are under 26 inches OAL. But they can be turned into a rifle, so why can't an AR pistol?

There's actually been some debate about his on the AR forums.
Part of the debate also centers around sig brace "pistols" with an OAL over 26" that could be considered "other" vs pistols and if that makes a forward vertical grip legal or not.

In both instances, is seems nobody wants to be the test case.

It does.

So you can turn an AR pistol i to a rifle and back again?

Yes

Not that I would suggest anything illegal, but who is going to know if it was once a rifle or once a pistol?

Got the go ahead this weekend to build "My Wife's" new Sig Brace gun.

The first piece is now in inventory.

An Odin Works, 10.5" stainless, medium weight .223 Wylde chambered, button rifles, Carbine length gas, barrel.

I suspect the ATF would know. If it was entered into the manufactures bound book as a rifle then you will have a problem.

As the brace is a work around I personally would pay very much attention to my Ps & Qs. They might not have much of a sense of humor.

I didn't know manufacturers would do that. Are the markings or serial numbers generally any different?

By bound book he's referring to the form 4473.

if you buy a lower that is new and has never been built on they call it in as "undefined" vs. handgun or long gun.

so, buy a lower and build.

if you ever sell it and it goes through a dealer as one or the other, then that might be a problem, but I still can't see how ATF would know...

That was my train of thought also.

ETA: After reading up on it, if you start with a stripped receiver, there is no way to tell if it was once a rifle or pistol. So, you may be breaking the law, but there is no way anyone would know by looking at it or tracking paperwork.

If you buy a brand new unbuilt stripped lower and build it as a pistol! It. Has to be marked other on the 4473.

The law is that a rifle cannot be made into a pistol. They have to have some proof it was a rifle and you converted it. You have no obligation to prove it was not a rifle. However, your idea of keeping a copy of the 4478 seems sound.

Nice piece, but I think I'd rather have a bullpup rifle in 5.56 than a pistol version.

MSAR

MM

That's another fun looking option.
Personally, I decided to stay standardized on the AR platform.

Yeah, I have so far, too, but the smaller piece sure makes a nice CQ or vehicle option.

MM

No.

I am referring to the "bound book" all 07 FFLs(manufactures) are required to keep. I have 2 of them and every firearm we manufacture is listed in these "bound book" along with the disposition of said firearm.

When we manufacture a lower it is recorded as a receiver. If we later sell it as a completed rifle it is recorded as a rifle.



Simple back trace.

If the 07 FFL (the manufacturer) logged that gun into his "bound book" as a rifle and you install a Sig Brace and a 12 inch barrel you are in trouble. Has nothing to do with the 4473s.

Your rifle has been recorded as a rifle.

Simple back trace just like when a gun is found at a crime scene.



The 4473 is not the controlling document. If the firearm has ever been logged into any FFLs bound book as a rifle you will have an issue if the ATF does a back trace.

Just saying be careful as this is a very easy check for the ATF and the Sig Brace is sure to draw scrutiny.

I hear you regards the bullpup however for my thinking are they not pretty specialized designs, how do you replace the trigger etc. The Tavor I picked up did not seem like a LW???

FormD has a point regards performance against std pistol rounds. Stolen off the interwebbs below just got me thinking..

9 inch 223 (M193) is 2591FPS with 820ME, 9mm pistol (115grain) is 1250FPS with 401ME, 45ACP (230grain) is 950FPS with 461ME, 9 inch 300BO (110grain) is 2116FPS with 1094ME.

I may be wrong as I often am wrong, yet to my thinker the BO makes good ballistic sense in a pistol.

John a brand new in box stripped lower receiver from the factory is sold as "other" marked in the bound book as "other". It has never been made into anything. It is in the original box that says "lower receiver stripped". The tag on the receiver says NEW. The SN on the box matches that of the enclosed "new" stripped lower. That new stripped lower from the factory when built into a pistol will be a pistol.