quote:

Originally posted by MikeinNC:
^^ihave a AR pistol for this exact issue..
1. It can be transported across state line w/o a letter from ATF
2. It can be shouldered
3. It does not have a stock (it has a brace)
4. I didn’t have to have a stamp

Mines a switch barrel and I have a 10” 300BLK barrel for it and it came with a 5.56 barrel

I put a law adapter on it and it fits into a computer bag and can be assembled in less then 30 seconds.

If there is ever a question the ATF can look up the serial miner and find it was made and transferred to the wholesaler and the 4473 and see it was sold as a pistol.

No stamp
No engraving

Those are the exact reasons I chose to go with a DDM4PDW. It started life as a pistol and was transferred to me as a pistol on the 4473. No stamps were required and I can fit it in a backpack, without the need for reassembly.

I also appreciate that if I want to, I can grab another upper for it, slap it on and I’m good to go (continuing as a pistol). I could definitely see a 10.5” 5.56 upper in my future…

quote:

Originally posted by MikeinNC:
^^I have a AR pistol for this exact issue..

Mike, you’re either contributing to my distraction, or adding another project (aka: way to spend money) to my list.

So following the rest of your post… I’ve got a stripped lower in the safe that I bought a while back and haven’t done anything with. I don’t have any reason to think it was transferred as a pistol, so I’m thinking I would not be able to use it to build up a pistol. Instead, if I wanted to build up a pistol in the future, it seems I’d have to buy another stripped lower and have my FFL specifically mark it as a pistol at the time of transfer. Is that right?

A 'stripped' Lower Receiver should be transferred as an 'Other Firearm' (Frame, Receiver, etc). You can build anything you want with it!

See Box/Question 24 in Section C, and the Instructions on page 6 of ATF Form 4473 --> https://www.atf.gov/firearms/d...-form-53009/download


For the Record - While you 'can' shoulder a pistol, there is NO Brace on the market that truly shoulders like a proper Shoulder Stock! And while one can definitely have use cases that justify an AR Pistol (No hassle transporting across 'most' state lines, and depending on state law/the state's definition, 'loaded' while in a vehicle are primary IMO), it's NO substitute for an SBR.

I bought a pair of Anderson stripped lowers some years ago but I don't recall how the 4473's were marked. Is there some way to view or download an old 4473 from the ATF?

Also, when I get to building my SBR, would I be better off to build a new lower on one of those Anderson receivers, or use an already-built Rock River lower that I've been shooting (with a 16" upper) for 15 years? The latter doesn't have a ton of rounds through it, but it's always functioned perfectly.

Expert308, your line of thinking is very similar to mine.

I think I’ll be better off to use a fresh lower, given that it’s got to be engraved and will be “dedicated” to that build. I’d keep an existing (“used”) lower in service as-is.

First, re: the original 4473, if I'm a betting man, it's unlikely you'll be able to get your eyes on that. It would be in the possession of the FFL, unless they are no longer in business, and then it would have been turned over to the ATF. Regardless of who has it, unless it's part of a criminal investigation, you'd be unlikely to find anyone receptive to your request. Depending on how long ago the lowers were purchased, and how good of a relationship you have w/ your FFL, you 'might' get lucky though.

Re: which Lower Receiver, I could be wrong, but I've not heard of an in spec, properly assembled & maintained Lower Receiver wearing out. As such, 'fresh' vs 'used' wouldn't be a consideration for me. If I were paying for a $200 Tax Stamp, I'd definitely be building an SBR w/ the RRA Lower Receiver! Considering the zero $ tax stamp, it wouldn't/doesn't really matter.

If you are buying or building an upper in .300 Blackout…no matter what length of barrel you choose, I highly recommend it be equipped with a pistol length gas system…I currently have four 300 BO uppers with barrel lengths from 7.5” up to 16”…I have pistol length gas systems on them all and function is perfect…I have several friends who used carbine length gas and have cycling issues with some bullet weights…ie. heavy bullets in subsonic loads especially with 16” barrels….300 BO is actually my favorite AR15 chambering especially since reloadable brass cased ammunition prices have been slowly dropping as of late…my favorite barrel length is the 7.5” for all around shooting…as far as lowers are concerned, every stripped lower I have purchased in the last 10 years or so were transferred as “other” on the 4473…the aforementioned Anderson stripped lowers have been very good on the builds I have used them on…however my favorite “affordable” lowers have been AERO and Ballistic Advantage…another thing is that dedicated .300 BO magazines function better when using heavier bullets for subs and mark them legibly to keep from accidentally mixing 5.56 with .300BO…however as with most things…your mileage may vary …an informative website on the .300 BO is the…

https://www.300blktalk.com/forum/

quote:

Originally posted by Bisleyblackhawk:
If you are buying or building an upper in .300 Blackout…no matter what length of barrel you choose, I highly recommend it be equipped with a pistol length gas system…I currently have four 300 BO uppers with barrel lengths from 7.5” up to 16”…I have pistol length gas systems on them all and function is perfect…I have several friends who used carbine length gas and have cycling issues with some bullet weights…ie. heavy bullets in subsonic loads especially with 16” barrels….300 BO is actually my favorite AR15 chambering especially since reloadable brass cased ammunition prices have been slowly dropping as of late…my favorite barrel length is the 7.5” for all around shooting…however as with most things…your mileage may vary

Prices have definitely been getting better. My DD has a 7” barrel and I’ve had good results using the 147 gr Winchester FMJ white box bulk stuff. I’ve been getting it for about $0.62 per round lately, which is a lot cheaper than it used to be.

quote:

Then this afternoon I saw an ad at Palmetto for a 9” pistol upper for $200 or so. As I understand it — and this is where I need solid advice — a pistol upper mated to a lower and a stock is essentially an SBR. Is that correct?

I know the OP's concerns/questions have been addressed, so I won't discuss those but only want to point out the error of calling the upper a "pistol" upper. An upper by itself is just that, an upper. It could be a short-barreled or long-barreled upper. There is no such a thing as a pistol upper or a rifle upper. It's what you do with it determines if the final product is a rifle (put it on a lower with a stock) or a pistol (put it on a lower with a brace). For example, a 16-inch barreled upper on a pistol lower is technically a pistol, not a rifle. Barrel length is irrelevant.

The "pistol" in the PSA ad refers to the length of the gas sysytem, not of the barrel. The .300 BO has a pistol-length gas system.

Vthoky, you are correct. If the receiver was purchased naked, then it would be listed as “receiver” or “other firearm” on the 4473. And you can build whatever you want.

My Diamond Back AR pistol has a larger diameter receiver extension tube than a carbine or rifle tube and you can’t put a rifle or carbine adjustable stock on it w/o removing and replacing that tube.

But I’ve seen SB tactical braces that are adjustable and are the same diameter as the rifle/carbine tube.

quote:

Originally posted by nhracecraft:
…For the Record - While you 'can' shoulder a pistol, there is NO Brace on the market that truly shoulders like a proper Shoulder Stock! And while one can definitely have use cases that justify an AR Pistol (No hassle transporting across 'most' state lines, and depending on state law/the state's definition, 'loaded' while in a vehicle are primary IMO), it's NO substitute for an SBR.

Of course, a brace is a brace and not a stock. But for probably millions out there who don’t care to jump through any more government hoop than they need to, the AR pistol serves as a substitute for them just fine.

quote:

Originally posted by MikeinNC:
Vthoky, you are correct. If the receiver was purchased naked, then it would be listed as “receiver” or “other firearm” on the 4473. And you can build whatever you want.

quote:

Originally posted by 12131:
want to point out the error of calling the upper a "pistol" upper. An upper by itself is just that, an upper. It could be a short-barreled or long-barreled upper. There is no such a thing as a pistol upper or a rifle upper. It's what you do with it determines if the final product is a rifle (put it on a lower with a stock) or a pistol (put it on a lower with a brace). For example, a 16-inch barreled upper on a pistol lower is technically a pistol, not a rifle. Barrel length is irrelevant.

The "pistol" in the PSA ad refers to the length of the gas sysytem, not of the barrel. The .300 BO has a pistol-length gas system.

Thank you, Mike and Q. I appreciate the clarification.

As I’ve said many times before, I’ve got a lot to learn and I do appreciate “the SIGforum team" helping me to learn it.