AR-15 pistol question

[10-Ring]

I understand that if I want to build an AR-15 pistol from a stripped lower that I have to designate the lower as a pistol on the 4473.  Is that correct?  If so, if I buy a stripped lower in a FTF transaction is it automatically ineligible to be built as a pistol?  I have no interest in skirting the law as I have never seen a ATF agent with a sense of humor.  I just don't understand how if we don't have registration how I would prove that my AR-15 pistol was built legally.

[cz75b]

if new it doesnt matter what its designated on the 4473,because at that point its not been assembled.all you have to do is assemble it as a pistol first then you can pretty much switch it back and forth between pistol rifle at will.if getting one used im not sure how they would go about it,but if it could be proven that it was assembled as a rifle first and you made it into a pistol then you would be in violation of something.

[10-Ring]

Yes, from my understanding once a rifle always a rifle but a pistol can go back and forth.

[cz75b]

yes

[Oh Shoot]

I understand that if I want to build an AR-15 pistol from a stripped lower that I have to designate the lower as a pistol on the 4473.  Is that correct?  If so, if I buy a stripped lower in a FTF transaction is it automatically ineligible to be built as a pistol?  I have no interest in skirting the law as I have never seen a ATF agent with a sense of humor.  I just don't understand how if we don't have registration how I would prove that my AR-15 pistol was built legally.

 
Any lower, new or used, should be marked by FFL as "other firearm" on question 18 since 8/2008. However, what an FFL puts on 4473, correctly or incorrectly, doesn't actually determine legal classification of a firearm, nor the legality of a particular future configuration of it.
 
The only federal requirement for legality to make a pistol is that the lower did not begin life as a rifle, either by retail manufacturer, individual, whatever.
 
The burden of proof to prosecute you for making a firearm from a rifle falls on the prosecution. Quite easy if you built a pistol from a used lower that left the manufacturer as a rifle. Virtually impossible if the rife were first configured by an individual gun owner who bought a new lower (unless the guy wanted to rat you out :).)
 

Yes, from my understanding once a rifle always a rifle but a pistol can go back and forth.

Not "once a rifle, but "first" a rifle, always a rifle. If first configured as a pistol, can be either from then on.
 
- OS

Edited October 17, 2014 by Oh Shoot