I have a form 1 that was approved in Colorado (where my trust's permanent mailing address at a family member's house is located) for a SCAR 17, but I have since moved to Alabama. The SCAR is still wearing its factory 16 inch barrel. When I finally get around to swapping it out for the 13 inch barrel, do I file a form 20 to move it as an SBR first, or is there something else I should do? And how should I engrave it (Colorado or Alabama)?

Okay, so it sounds like I should be good if I file a form 20 to "move" the rifle to Alabama, engrave it:

MY TRUST
MY CITY AL

...and then finally swap barrels.

Thanks!

Can you link to this so I can read it? TIA.

Edit: found this.

27 CFR 479.102:

(a) You, as a manufacturer, importer, or maker of a firearm, must legibly identify the firearm as follows:

(2) By engraving, casting, stamping (impressing), or otherwise conspicuously placing or causing to be engraved, cast, stamped (impressed), or placed on the frame, receiver, or barrel thereof certain additional information. This information must be placed in a manner not susceptible of being readily obliterated, altered or removed. For firearms manufactured, imported, or made on and after January 30, 2002, the engraving, casting, or stamping (impressing) of this information must be to a minimum depth of .003 inch. The additional information includes:

(iv) In the case of a domestically made firearm, the city and State (or recognized abbreviation thereof) where you as the manufacturer maintain your place of business, or where you, as the maker, made the firearm; and

I actually found the quoted language in one of your old posts.  Appreciate it!