Sorry guys I'm sure this has been covered. But just need a quick answer, PSA has lowers on sale for $49 and I ordered one to have on hand. I'm thinking of  a 300 blackout  can I make a 300 blackout pistol out of a regular lower? Again sorry for the newb  question

As long as it is an unused lower yes you can. If it was once a rifle then the answer is no.

Thanks for the quick reply. I just finished my first build. Just a 16" 556 and bought this lower quick when I saw it for $49 and was trying to figure out my options of what I can do with it

Just a slight point of clarification. 


Yes OP, you can use the PSA lower for your pistol.

Yep.

What a convoluted cluster fk law.

Say what?

Please educate me.

What difference would it make if I take parts from one assembly and move it to another?

Thanks

RJ

None except the serialized lower itself.  

The lower, on first assembly into a functioning weapon, is defined as a pistol lower or a rifle lower.  There is no record keeping or magic.  A bare lower is defined as "other" no matter what the paperwork says.  After first assembly into a pistol, that lower may be used with a rifle or pistol, no consequences.  If a "rifle" lower is mated to an upper with less than a 16" barrel, you have a SBR even if you leave off the stock, or replace the receiver extension with a pistol only tube or use an "arm brace".  So if you buy a Ruger carbine with a 16" barrel that lower will forever be a "rifle" lower and if you put a 10" barrel on it you've made a SBR not a pistol even if you've got an arm brace or a bare receiver extension tube like a "pistol".  But the rest of the parts could be reassembled onto a bare "pistol" lower with a 10" barrel and now you have a pistol.

Every other part of the lower (except the serialized lower itself) is just a spare part and plays no part in the pistol/rifle classification of the lower after the first assembly of the lower.  

This is what I gleaned from lots of reading before I assembled my two.  

Short version, assemble every lower as a pistol first and take a picture.  After that do whatever you want with any of the lowers as long as you're not making an illegal sbr.  Stupid vertical grip/angled grip bs, don't shoulder the sig brace, blah blah blah.  Bunch of bureaucratic political stupidity that can land you in jail and lose your 2a rights if you screw up and piss off the bureaucrats so don't screw it up and don't poke the bear.  

From what I understand, it really is that insane.  That's what you get when politicians write asinine laws and then power mad bureaucrats interpret them for 83 years and force a weapon system designed 30 years after the law was passed to conform to the asinine law.