I currently have a 10.5 300 blk SBR.  I would like to use that upper on a pistol lower for the deer hunting season, since I live in a shotgun only zone but the do allow the use of pistols.    I have a unused lower receiver in my safe.  Can I build that into a pistol lower of does it have to leave the factory as a pistol.

I have been reading in this forum for a few days and have found conflicting information.    Any help would be greatly appreciated.

yes

Yep, you're fine federally.

Any prob with the "permit to purchase handgun" thang up there if you simply configure one rather than buy it from FFL?

- OS

MN requires you to have a permit to puchase a handgun just to buy any Ar15 including lower recievers.

Ok so as I understand it I can build a pistol lower into a rifle lower and use it with a 16" upper and then back to a pistol?  But I cannot build a lower into a pistol if it had been previously built into a rifle ?

No. Federally, there is no such thing as a "pistol lower" or "rifle lower". It is merely "other firearm/receiver". It isn't either handgun or long gun until configured as such.

If a virgin lower begins life as a pistol it can go back and forth between pistol and rifle. It it starts as a rifle it must stay a rifle. Whether bought complete as a pistol or rifle or configured from virgin lower.

Yes, I know, who would know if you built it yourself? But that's is the law, or at least the interpretation of it (as settled by the Supreme Court). So build the pistol first and all is good, eh?

- OS

I'm in on this!! I have 5 more stripped lowers, and now I've got a good reason now to build a pistol setup!

Thanks for all the replys. I just want to make sure I do it right.