AOW Modifications and possession nuances

[Modimo]

I need some help from the AOW experts out there...

When sending in Form 4, you report Model, Length of Barrel, and OAL (In the below examples we are basing it off of an AR Pistol that is being registered as an AOW)

If you want to change the upper, I understand you must always hang onto the original upper? I assume as long as you have ownership (no matter where it is- ie at home when you go to the range) you are ok?

Any permanent upper changes (ie selling old upper for a new one) need to be reported to the ATF, correct? If so, how is that communicated and confirmed?

What if you are making a small change (say, changing a flash hider for a brake that changes the OAL)? Does this have to be reported in the same manner as the above example?

Are you in the clear (not needing to report any changed) if you change an upper out for another that does not affect the OAL or Barrel length?

Lastly... More of a constructive possession question more than anything, but is it considered constructive possession owning more than one short barreled AR upper with one registered AOW (that it is able to mate with)? Let's assume for this example that there are complete built AR's as well as completed lowers awaiting an upper in the same location as the AOW.

Thanks in advance!

[ke6guj]

there is no regulation or law that says that you can't change the dimensions of your AOW. You aren't required to always have the parts to go back to the original dimensions. ATF requests that you inform them of any permanent changes, but that appears to just be a request, not a requirement of law.

[TangoCharlie]

You do not need to retain the original upper or configuration, this is an Internet myth.

The Form 1 is for making an NFA firearm, not for the continued possession of that firearm. Build the firearm per the Form 1 configuration, the move on, change uppers as often as you like.

There is no requirement to notify NFA Branch of any changes in configuration whatsoever. They merely as that you notify them if the change is permanent. And "permanent" does not mean you sold the original upper, it
means you altered a difficult to alter firearm, like one with a fixed barrel. NFA Branch really does not consider anything done to a modular firearm like the AR platform as "permanent" for this reason.

Regarding CP, the registered NFA firearm is your pathway to legality for any short uppers in your possession. You obviously do not want to install any short uppers on Title I firearms unless they are pistols.

[Modimo]

Awesome! Thank you very much!