NFA question- Integrally Suppressed Rifle

[Garciadavida]

I'm interested in building an ISR. I know for a form 1 supressor you need to have just the tube to start, right? So for an ISR, do I need to have the barrel attached to the supressor tube? What's the process for it? Thanks!

No, you do not build anything before the form 1 is approved. That is a crime. The process generally, set up your gun trust at www.azgunlaw.com (http://www.azgunlaw.com), then you will mail in a package containing the following to ATF: a copy of your trust, the completed form 1 in duplicate, and the $200 tax payment. In order to complete your form 1 though, you will need to know some basic details about what you are building...caliber, barrel length, overall length, etc. After you mail it to ATF, you sit and wait for several months until they return the approved form 1 to you. Then you can build it. You also need to engrave the name of your trust and your city/state on the item as well. Mr. Silencer in the east valley or Molon Labe in the west valley can engrave it for you.

[Garciadavida]

But as far as the "basic details", what would I write. I know the overall length has to be 16", but since the silencer/barrel are permanently attached, how does that work? What do I write on the form 1? Would the whole rifle be the NFA item? Just the upper? The Barrel/silencer? It's confusing to me.