If I build 9mm rifle (not an ar9, diy) with 16 inch barrel and its overall length without a stock is long enough not to be a sbr. Can I add an adjustable arm brace? If it's not considered a stock it cant be an adjustable stock and not count as an assult feature.
Any opinions are appreciated.
You may be mixing up federal and state level definitions/laws in your question in such a way that makes it all confusing.
You are asking about legality of attaching a pistol brace to a weapon with a 16" or greater barrel and an overall length of 26" or more. I think you are asking in the context of state law.
In MA all that matters is barrel length. The taxonomy is rifle, shotgun, firearm. Anything that fires a round that is not a rifle or shotgun is a firearm. The definition of rifle is rifled bore and 16" or greater barrel. In MA what you have is a "rifle".
The problem comes with application of the AWB. The AWB says "see federal of 13 sep 1994". That means we use federal definitions for what you have in your hand to evaluate federal AWB.
Federally you do not have a "rifle" because it currently cannot be fired from the shoulder. Frankly I am not sure what you have federally as it sits right now. That makes it hard to figure out which federal definition to apply to determine its status as an AW.
Lets pretend we use the federal rifle definition. Then you are limited to one evil feature from
- pistol grip
- flash hider or capable of accepting flash hider
- bayonet lug
- grenade launcher
- folding or telescoping stock
A pistol brace is not a stock per the ATF so it would not be an evil feature per above.
But I see three problems
- What you have is not a rifle under federal definition so application of the federal definition is questionable
- The disconnect of state and federal definitions results in chaotic application of AWB usually always in the way least favorable to you
- This is all far too technical for the people that will arrest, charge and prosecute you. This is MA. you are screwed
I also want to figure out what it is federally. It might just be a "firearm". It is not a rifle since 27 CFR 478.11 says it must be designed to be fired from the shoulder. It is not a SBR since 26 usc 5845(c) and 27 CFR 479.11 says OAL under 26" or barrel under 16". It is probably a firearm and therefore application of the federal AWB becomes interesting.