It's very nebulous as far as I can tell. However, that first kit includes a "stock", not a "brace". You can see the difference. The brace is a current ATF controversy at the moment. The stock is not - - I think adding a real stock to an AR pistol, as opposed to a brace, makes it an SBR from the outset, and you really cannot go back except for the obvious argument that if you take it apart nobody saw it so where's the law violation?

As far as I am aware, once you step over that line your only safe harbor is nobody saw it and you can make it disappear but the violation remains. It's like speeding. The fact that you drove 90 mph in a 45 mph zone and didn't get pulled over doesn't mean you didn't do it. Getting prosecuted for it is just not possible but the law was broken.

Another problem is that in the unlikely event you did have an ATF raid on your home the existence of a stock NOT attached to your pistol and not attached to a rifle is definitely going to raise ATF eyebrows. What they would do about it is hard to say and 99.99% of gun owners will never have to deal with an ATF raid, anyway. The real issue is if the ATF decides this company sold SBRs to folks without tax stamps they COULD follow the chain to the purchasers = they're in that .01%.

That's the view from my saddle, anyway.

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