Educate the moron about AR pistols?

Diamondback · Apr 12, 2017

Well, I've started to plan my first AR pistol build, and need some help getting up to speed.

First, what all limits do I need to stay within to stay "pistol" and not cross into "AOW"? I know a true VFG makes AOW automatically if under 26" OAL, but Magpul's AFG does not--I need to contact Mako Group and see if the FAB Defense PTK I hope to use has a Determination Letter like Magpul. (One would THINK it'd be OK, it's even closer to horizontal than the Magpul item! But never trust a BATFink...)

For the build I'm considering...
Tacfire pistol buffer tube = 8" (temporary part)
Buffer tower = 1/2" (assuming overlaps with threaded portion of tube)
Upper = ??? (uncertain of barrel overlap into upper)
Barrel = 10.5" (don't know if this includes factory A2 flash-hider)
Precision Armament AFAB-556 brake = 2.23", Indian Creek BFD = 2.5"

Also, any potential NFA issues from adding a LAW sidefold adapter into the mix? And do any of you AR pistol guys have suggestions about buffers, ported 10.3" barrels etc., that might help me refine Phase 2 of the build when I move it over to its "permanent" lower and turn this one and the Tacfire tube into a .22LR AR pistol?

Flopsweat · Apr 12, 2017

Don't use a lower that was originally a rifle. Don't attach a VFG or a stock. Don't put your pistol upper on a rifle lower. I'm pretty sure there are no minimum or maximum barrel length. Side folder shouldn't be an issue. And as always, this is just my opinion, not legal advice.

Kruel J · Apr 12, 2017

My first AR build was a pistol. 7.5". No FG at all. Phase 5 buffer tube assembly. It shot great. Just don't shoulder it!

I've wondered a few times how many AR pistols are made from lowers that were originally sold as "rifles".

NWMA · Apr 12, 2017

Law folder is not an issue.

Diamondback · Apr 12, 2017

I should note that the lower in this build is an EPL that I'm finishing myself, so it's never had a chance to be a rifle or really anything--and oh by the way for bragging rights I even cut some of it WITHOUT the hep of power tools.

Flopsweat · Apr 12, 2017

Diamondback said:
I should note that the lower in this build is an EPL that I'm finishing myself, so it's never had a chance to be a rifle or really anything--and oh by the way for bragging rights I even cut some of it WITHOUT the hep of power tools.

When I build a lower I build it as a pistol first, even if it's going to be a rifle. This way there is no uncertainty later as to what I can do with it.

Diamondback · Apr 12, 2017

Flopsweat said:
When I build a lower I build it as a pistol first, even if it's going to be a rifle. This way there is no uncertainty later as to what I can do with it.

Yeah, made that mistake with my NWFA lower... part of the purpose of this build is a parts-set to swap onto every future lower I buy or build.

Diamondback · Apr 13, 2017

Next question, what's the crowd's favorite buffer tubes and kits out there?

etrain16 · Apr 13, 2017

Well, you had me curious on the PTK - checked their site and no mention of a determination letter from the ATF. However, 2 minutes of Google Fu and I found this, which should answer your question regarding the PTK. You'll see in the highlighted area of the 2nd page that the ATF specifically lists both the Magpul AFG and the FAB PTK as allowable on a pistol and does not constitute an AOW.

Link to where I found this letter: The Law Office of John Pierce, Esq.

Diamondback · Apr 13, 2017

Much G, @etrain16

--I use DuckDuckGo and StartPage and neither hit that for some reason.

mjbskwim · Apr 13, 2017

Kruejl said:
My first AR build was a pistol. 7.5". No FG at all. Phase 5 buffer tube assembly. It shot great. Just don't shoulder it!

I've wondered a few times how many AR pistols are made from lowers that were originally sold as "rifles".

As many as have never been in a gun shop or gunsmith's books as a rifle
Or those that have never shown their serial numbers online

Not saying you should just take a rifle apart that has never been in those circumstances and make a pistol,by any means

AMProducts · Apr 13, 2017

So I just got done building something similar... Andersen Pistol Marked Lower I bought late last year (thankfully 2 days after trump was elected, so I only paid $50 ea for 2!!!!! WHOOOOO!!!!) I waited around and bided my time until a PSA 10.5" (I really wanted an 11.5") came up for the sale price of $199 wo BCG/CH, and added those, I already had a LPK that had been sitting around for some other build (I built a new gun >1yr ago and I bought a PSA build kit that came with an LPK) A local outfit had a Midwest industries pistol tube in stock with buffer for $55, and I had a DS-Arms quad rail sitting in my parts box. Fitted the upper with a Primary arms Microdot II, sitting on top of an old RRA low-pro carry handle sight, and I got an AR-Blade I use as a sling attachment point. (so I pull away from my shoulder).

It's goofy as hell, but its a lot of fun. I haven't done any weird folders, the "as is, where is" is fine. The MI tube is probably longer than it needs to be, but it works out really well. If I had to do it again, I would have just got the AR-blade kit, which has the tube and the brace.

Diamondback · Apr 13, 2017

That same Palmetto's on Easter Sale for $190 right now, so I'm thinking about one of those for an upper until I can find a ported 10.3" (I really wanted a Mk 18, but Daniel Defense's prices are in the same "Just Because We Can, Since We Got MIL Contract" territory as KAC).

Current "interim" plan / final:
EP Armory blank / Tennessee Arms Liberator blank
TacFire cheapo pistol buffer kit / ???
PSA 10.5 pistol upper / roll my own using undetermined 10.3 FSB barrel, maybe Andro Corp unless they can build me a 10.3 FSB upper
VLTOR CASV-EL EOD-style handguard / moved to new upper
FAB PTK foregrip and AGF-43 folding grip / moved to new lower
Precision Armament AFAB556 brake / moved to new upper
ICD BFD flashcan / moved to new upper
--- / LAW sidefolder
undetermined RDS or holosight
Concept is for this evil little beast to be a briefcase/duffel-carry/PDW, something for those cases that are too much for my old duty 1911 but not enough to break out the Ten Pound Monster Carbine... then I need a name for this build, some kind of nasty little green critter that will totally eff you up if provoked.