Using "carbine" buffer tube on an AR pistol - does that make it unregistered SBR?

I am in the process of putting together an AR pistol and would like to use the Battle Arms Sabertube for my buffer tube. BA makes several different Sabertubes which are identical in every way except length: pistol, carbine, and rifle. And of course, the carbine and rifle lengths also include a removable miniature “stock.” I am asking this question because I have a 6’6" wing span and would prefer a longer buffer tube for comfort. Can I legally use the carbine or rifle length tubes on an AR pistol?

http://www.battlearmsdevelopment.com/sabertube-tm-qd-end-plate-bad-lbs-lightweight-stock-combo

These buffer tubes have no detents at all for any conventional stock. They include a minimalist “stock” which I would of course remove before assembly. I would replace it with an approved pistol brace.

Thoughts? Is this kosher or would I be assembling an unregistered SBR, in which case, big no no.

I would personally wait until either a status letter is released from the ATF technology branch, or they sell the tube with no stock portion, advertised and marketed as a “pistol” tube.

How much longer of a tube are you looking for? The Vltor A5’s both pistol and rifle are 3/4" longer than a regular carbine-length, and the KAK tube is just as long but only bored to the same depth as a standard CAR.

The longest pistol buffer tubes I can find are 9" OAL (so about 8 and 1/4" extension beyond the receiver). I would like to have around 11" of extension. I have a LAW Tactical folding adapter on order which should help.

And from a purely asthetics standpoint, those dimpled Sabertubes are niiiice. A perfect match for a dimpled KAC CQB upper…

I was wondering why it felt like I had longer adjustments with the dimples then a standard 6 position!

Thanks for this random tidbit, great piece of cool information that could be helpful.

Nonetheless, I dunno…

If you buy the “stock” I would imagine it could be discerned as potential “intent” if the stock is available to put back on it?

I am not sure. Honestly, I dunno if it would hold up in a court, if it ever even went that far. If you put a brace on the tube and crank it down. I was under the impression you could use normal carbine buffer tubes as long as you didn’t put a stock on it.

I may be misinformed though, and I go the KAK route for the 2 pistol lowers I have built out now. I also got a Phase 5 from a very generous member from the PIF forum awhile back. That goes on every lower I ever purchase and I “register” it as an original pistol lower in my excel file.

You know… Just in case? :ph34r:

I suppose, the bad news on that, is that I have to get a permit to purchase from every person I ever sell them too now as they are a “pistol” lower… Good news is I probably will never sell the nearly 10 lowers I have at this point.

Consult an attorney.

Conventional wisdom: buy rifle length. Use A5 system. Store stock at someone else’s house until your form 1 is approved.

Get a Law Tactical folder to increase LOP for the tube. Then you’ll have a folder too.

Or if you can stop looking at the shiny dimples of a BAD tube, get a KAK shockwave and pistol tube and extend the brace as far out as you want.

Perhaps buy it remove the stock piece and have a friend hold on to it at their house?

Edit… do what fledge says.
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Or build with a LAW folder and an A5 Pistol Kit, then run the brace out–all the tube length, plus the operating benefits of the A5 recoil system. :slight_smile:

The BAD rifle length is the same as the A5 pistol tube. Just run the A5 buffer and spring in the BAD. :wink:

Thought we were trying to avoid anything that even might be classed as SBR until the Form 1 gets approved, though…

Yes. Just don’t put a stock on it.

You can put stocks on. I use the KAK Shockwave Blade. Works pretty decent.

Not a stock! Never a stock!

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OK. True. It’s a brace.

[emoji106]

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