I recently purchased a lower thinking I was thinking I was going to put together a rifle so the 4473 was call in as a long gun but was never put together, I decided that I want a pistol so do I need to find an FFL and do an other 4473 to make it a pistol lower?
Stripped lower or completed lower?
On their form they usually (and should)mark stripped lowers as "other" so that u can make it into what you want.
If it's a completed lower (like those PSA blem lowers), then I **think** it might have to stay as a rifle.
Someone will come along shortly and straighten us out.
There's a saying... if it started as a rifle, it has to stay a rifle. .. or something lie that.... anyone? I'm just rambling now
ALL lower receivers (bare receivers in general) are ran as an "other". Doesn't matter if a buttstock is installed from the factory or not.
Even though "once a rifle/long gun always a rifle/long gun" applies, you still have to be 21 or older and a resident of the state to buy a lower....even though it is considered a long gun if a buttstock is implied.
This is one of those "clear as mud" type ATF rules. About as clear as "now you can shoulder your sig brace."
A few years back your local FFL had to choose whether the new AR-15 you were making was "rifle, pistol or other." Today, they're all "other." At least, they should be. Even with a stock attached it's still "other" when they call it in. If yours was called in as a long gun then you can't make it into a pistol. Ever.
Your best bet is to buy a new one (stripped) and have it called in as it should be - "other." Then you can make it into a pistol with no issues. You can make it into a rifle if you want but once you do, you can't go back to a pistol. Ever.
I reckon in a few years we'll be able to do whatever we want with the lowers. Until then, play by the rules so you don't get shot.