Quoted:
This question comes up A LOT.  The correct way to LIST a stripped lower on the form 4473 is "Other."  You may build anything you like out of it.  Be aware that if you assemble it first as a rifle (has a stock), then it's a rifle and you can't legally put a short barrel on it without a stamp. Build it first as a pistol and you can put a short barrel upper on it, but NOT a stock.

Quoted:
Once you put a stock on a lower it essentially becomes a rifle. You can take a lower and build it to whatever you want.

But it has to be at least 16'' Overall barrel length to be a rifle and anything shorter has to be a pistol unless you get a tax stamp for an SBR via FORM 1.

Quoted:
I purchased a lower this weekend and when I went to the FFL dealer to pick it up he registered it as a lower.  I plan on building a 223 pistol with it so I told him I needed it registered as a pistol.  He looked confused and said you do know this is a lower right.  I said yes but I plan on making a 223 pistol.  He said that when he does the paper work he does it as a lower.  Is this correct?  Can I build a pistol with it?  Thanks

Quoted:
There is a reason why you have to be 21 to buy a stripped receiver.

Making it into a pistol is one of those

Quoted:
I'm the Director of Compliance for a FFL in California, maybe I can help.

You must be 21 to buy a stripped AR15 lower receiver because it can be made both into a pistol and a rifle.  At that stage in the game it is listed on the 4473 as a "receiver" and caliber is "multi" because both the type of gun and its caliber are not established on release day.

Building that lower into a built lower with a stock still does not constitute being a rifle by the ATF -it is still a "receiver" on the 4473 and legally has no bearing as a rifle or pistol yet.  We must do multiple release forms when anybody gets released 2 or more handguns and/or 2 or more detachable mag, centerfire, semi-automatic rifles within a 5 day period.  A customer can buy as many stripped or built lowers as he wants within a 5 day period but we still don't have to fill out either multiple release form because the feds don't regard stripped or built lowers as rifles or pistols yet.  Tracking?  Okay good.  Moving on.

The Feds dictate that if that lower is made into a rifle (with a stock and a barrel 16" or longer) then it must always remain a rifle and can never be made into a pistol.  Making a pistol out of a rifle is BAD NEWS unless you got some extra money, stamps, and time.  You can choose to make your lower into a pistol and then later make it into a rifle, but yet again, once it becomes a rifle it may never go back to being a pistol regardless of whether it started as a pistol or not.

To summarize (on a Federal level):
-Making an AR pistol after you've already made it into a rifle (that had a stock and a barrel of 16" or more) = BAD
-An AR with a stock with a barrel less than 16" (without NFA/SBR stamp) = BAD
-Taking off the stock and turning a built lower into a pistol (if it's never been a rifle) = OK
-Taking an AR pistol and putting a stock and 16"+ barrel on it to turn it into a rifle (so long as it never returns to being a pistol) = OK
Depending on your State, you may have further complications such as handgun registration and things of that nature that may impede what the Feds say.  Remember, when dealing with guns, the Feds are the baseline and the States can (and do) pile on whatever else they want to make things harder.  

Hopefully this helps.  The best thing to do (especially when building AR pistols) is to "float" the upper and lower together but not snapped together, take a picture of the upper floating the lower, and send the picture with a letter to the ATF basically asking "is this legal?"  It may take some time for them to get back to you, but they will tell you "if you were to snap the two together, assuming it stays as the picture shows, and the gun has never been a rifle, then yes, it would be legal."  Get that letter for your exact setup and never worry about it.  If you live in enemy territory like I do, keep that ATF letter with the gun when you go to the range in case you get pulled over and the street cop has no idea what he's looking at (which is all too common here).  

Quoted:
You can technically go back and forth from pistol to rifle and back again if and only if the "virgin build" was a pistol from the start, but it's not advisable.  Too much California has rubbed off on me, because that's a no-go for here.  As stated, get a letter.

Quoted:
I don't really get the whole "If you get a lower that is filed as an [other] on the 4473 and build it into a rifle it is a rifle" thing. Someone please elaborate. Explain how though, in my state firearms aren't registered, that if I take a lower that I have been using for years as a rifle and then put a 7" upper on it WITH a pistol buffer extension, it is illegal. The firearm was never noted as a rifle in any way and now follows all rules regarding the pistol designation. Sure, I may have a 16" upper in a closet with a stock and buffer extension, but last I checked that was not illegal.

I understand that taking a complete rifle that I purchased as a rifle and swapping all the parts out could be frowned upon, but even then, as long as the firearm meets all requirements of it's current designation, I fail to see how it would find me in jail, (barring someone has a complete lower in rifle configuration and a complete short-barreled upper separate in a safe). Once again 4473s are only kept in my state for around 3 years (as told by a couple different dealers) so after that timeframe who would be able to tell that the original rifle was purchased as a rifle at all?

Quoted:


Thompson Center won this for us.  I built up my Stag lower as a pistol, solely so that I could one day build that Stag lower back into a pistol after whatever its intermediate designation was.



First, I got the certificate of virginity from Stag.



Then, I built it as a 16" bolt action pistol w/ rifle buffer tube - I did not then, & still don't, own an AR rifle stock.



Last year, I converted my bolt action AR pistol to a semi-auto rifle w/ collapsible stock - same 16" bbl, but it's now shorter than it was as a pistol.



Its next configuration may be as a PG shotgun or a "firearm" over 26" w/ a VFG.  Then, who knows, I may make it a pistol again.



You don't buy a carbine kit from T/C for your Contender w/ the expectation that once you build it as a rifle, it will never be a pistol again.  Nor do you do so with a Beretta Neos carbine kit. California laws are in violation of the 2nd Amendment to the Constitution of the United States, and do not apply in the Free States.