If I SBR a .556 can I swap barrels to 300 BLK or vice versa? Does the lower need to be labeled a certain way? Multi Cal? Thanx for your help.

On a Form 1 question 4c must have one caliber, 4e must have one bbl. length, and 4f must have one OAL. Additional calibers, bbl lengths and OALs can be entered into 4h.

Whatever the lower says the paperwork has to match. After its approved you can put any upper you want on it

Ok, so as long as I know my intentions and scenarios before hand it's all legal with one tax stamp?

Once you build in the configuration the form 1 states you may change the  configuration however you like. You must engrave the lower with creator of the sbr( that would be you or the trust name) city and state where it was made. The sbr has to have the caliber marked somewhere usually people use the barrel marking and don't engrave it again.

This thread is full of absolute bullshit and misinformation

FORM 1 has ONE configuration. List the configuration of the original 5.56 setup. The caliber marking listed on Form 1 is whatever is listed on barrel NOT the lower unless of course they are the same. 4H is left BLANK unless you have something like importer markings.

Once you've made it you can legally reconfigure it however you please.

The ATF asks that if you permanently modify the configuration that you notify them in writing, but there is no legal requirement and technically nothing is permanent with an AR.

Is 4c lower caliber marking or bbl caliber?

The ACTUAL caliber. It's typically engraved on the barrel and the lower. Both are legal but for the sake of your SBR, use what is engraved on the BARREL.

Are you e-filing?

If so- go here:

http://www.ar15.com/forums/t_6_17/441796_Visual_guide__How_to_fill_out_a_Form_1_using_EFORMS__New_Thread_.html

If not- why not?

I wouldn't agrees with your first statement as everything I said is true.

I said "is full of"... Not "is ALL"... Your statements were valid.

Gotcha. As full of great information this site is. It sometimes amazes me how wrong some can be. Especially with NFA items.

yes. I just filled out my form 1 and called in for the answers. I didn't wanna be legally limited to any one upper on my SBR lower.

I'm just stating what Dianne with ATF told me when I called in. She said she gets these questions alot. So on the lower it would typically be marked "multi cal". And yes "technically" you can "legally" change your setup however you like but when it comes to firearms you can also go through legal nonsense and face prison time even when you do things within the law.

for instance, I can legally have a complete lower as well as a short barrel complete upper and be within my legal rights. At the same time I could also go to jail for that because of "probable cause" to assemble an illegal firearm or some nonsense like that.

And when it comes to NFA items why even risk it? again I called in.

Unfortunately what Diane (I've never dealt with her) told you on the phone is not the law.

There is no such thing as a "multi" caliber SBR on a form 1, engraving multi on your lower has no legal precedent. The Form 1 is an application to MAKE. When you MAKE a firearm, unless it has multiple barrels and trigger mechanisms installed simultaneously, it has a SINGLE caliber, barrel, and overall length. This has been covered AD NAUSEUM on this forum. When people ignore what NFA owners have been doing correctly for years, they undermine the precedent that we've set and the ATF has come to expect. When the NFA contracts out their work to random new examiners, who don't understand NFA and have been dealing with incorrectly filled out forms, we end up with a ton of confusion and weird legal assumptions.  

Refer to what is written and published in the NFA handbook or ATF FAQs. Those documents are WRITTEN guidance, which have been vetted through ATF legal branch. In addition, follow the experience of people who have been doing NFA for a long time. (Guys like TONY_K)

The part about owning a spare SBR upper with a non-SBR AR is internet fear mongering BS. Always has been. If the ATF is raiding your house, you already fucked up.

List only one caliber, barrel length, OAL
leave 4H blank
Engrave your name/city on lower

I can guarantee you will never go to prison for "probable cause". Absolutely BS.

And you are not within your legal rights to possess a lower and short-barrel upper, all other things aside. That's a possession violation under Constructive Possession, well-established.

Homeinvader +1

Leave 4h blank, hellbound's response is correct.

So much misinformation...

Can't even trust people at the damn bureau who get paid to answer these questions. My bad for being apart of the dispersing of misinformation.

Learning to trust the community doesn't always come easy but thank you for clearing everything up.

You are talking about the practicality of getting caught, not the legality itself. Constructive Possession is undeniably real and shouldn't be thought of as a crackpot irrational fear that will only come to fruition if raided by ATF. Most cases actualy don't come from active investigations, but unrelated discovery.

Constructive possession only applies if the ONLY configuration you can have with said part is an illegal one. I can have 10 SBR uppers as long as I have one SBR lower or pistol, even if I have 10 assembled lowers with stocks and no uppers, as those 10 SBR uppers have a lawful use, on my one SBR lower. Now, if I actually attach those SBR uppers to one of my non SBR rifle lowers, then I have committed a felony. Just having parts that CAN be assembled into an illegal configuration is not enough, only if the ONLY possible configuration is an illegal one, then you have constructive possession.

I wrote "exactly", then noticed something else in your post.

We're getting way off-topic for the OP, but the "firearm" is the focus of CP, not the part. While you are correct for a single firearm condition -as in a single receiver with multiple barrels allowing configurations inside and outside the NFA-, the courts have never addressed the particular situation you refer to.  Having a registered SBR covers that SBR, but having spare short-barreled uppers and complete lowers with stocks is not a condition covered in Thompson/Center or any other SCOTUS case. In all likelihood, CP could and would apply to the spare buttstocked lowers you refer to as they can only be assembled in an illegal configuration with a short-barreled upper. Again, nothing wrong with having spare short uppers for your SBR, but the registered SBR is irrelevant to other firearms you may have in your possession.

What if I am registering just a lower receiver as a SBR...so no barrel caliber info to use.??

Ok...so I put down what I intend to build on it?

Yes whatever configuration you are going to build.

The reason it has not been addressed, is because it is not illegal. Can you be charged with a crime because you possess the tools or equipment to commit that crime only? No. Should you be charged with rape because you have a penis? Or theft because you have hands? How about DUII, because you own a car and possess alcohol?  The point is, constructive possession is a legal theory based on the principal that owning an item, which CAN ONLY BE USED to create something illegal, is in and of itself illegal.

To break it down, it is LEGAL to own partially assembled rifle lowers, they are just parts.  It is legal to own multiple SBR uppers, if you own an SBR lower or pistol lower to accept those uppers, they are just parts.  The number of spares is not dictated by how many rifle lowers you may own or how many pistol/SBR lowers you may own, they are just parts. As long as those PARTS have a legal and lawful use, it matters not that there is also a POSSIBLE unlawful use. You break the law when you committ the crime. Or else I should worry about getting a DUII while I'm also transporting alcohol

The assembled lowers with buttstocks are what would be the basis for a possible criminal charge when the short uppers are the only uppers available to complete assembly. A legal use for the spare parts is not the issue, otherwise simple "collecting" would cut through and eliminate any CP vulnerability since collecting is perfect legitimate and legal. But it is not the case as case law presumes parts are merely part of a whole. Here it's that the lowers themselves can only be fully assembled in an illegal configuration because all that is available a short-barreled upper. Make sense? Not saying it's black and white illegal by any means, I'm saying that the clarity and precedent provided by U.S. v Thomson/Center covers the presence of only a single firearm with multiple barrels. It does not extend to a multiple firearm scenario like this.