I don't have the link but there's a letter from BATF dated Nov 2004.
On the time of purchase, if the lower was stripped, or never been rifle stocked, it can be registered as a pistol and will remain a pistol.
Here's the a question -- if I make the lower PISTOL and attached a stock and proper barrell lenth, is this legal. Its like having those carbine conversion for glock and 1911 -- meztech. They use a lower receiver pistol and make it into a pistol grip rifle. UMM
I bought two stripped DPMS lowers at local store. $252.40 out the door. Bonus -- they were consecutive serial numbers. Don't see that often. I registered one on the form 44*** (form to purchase gun)as a pistol and one as a rifle. Last two digits was 16 and 17 so I registered the 17 as a pistol -- I'm naming the rifle sweet 16.
thanks for all the good info -- now I need to search for parts kit and uppers -- anyone have spare parts for sale or trade.