AR based PDW build; input requested
I am going to build a AR based PDW (NFA reg SBR). Want something small and handy in confined spaces. Unsure what barrel length that I should go for. Before I can start the ball rolling, I need to settle on a barrel length for the Form 1. Here are the choices that I am looking at:
It will get a Magpul CTR stock. Troy flip sights. Comp M3 on a LaRue mount. If 9" or longer will get LaRue Handguard. LaRue LT-FUG foregrip.
I already have a registered M16 with 12.5" barrel.
What's everyone think?
Can't you write various on it, kind of like the caliber? I remember hearing people could write that on the blank for caliber if they had a bunch of uppers.
7.5" bbl chambered in 7.62x25.......thats what i want.
Originally Posted by 
I don't think the ATF is cool with MULTI. when you fill out your stamp I think you need to pick One caliber. I'm no expert I just sent in my form 1 I wanted to put 5.56mm,9mm,22lr but I didn't want to have to wait extra months because I fill it out wrong so I just put 5.56mm. Some other forms I've read said you have to pick One caliber on the Form 1 but once it is approved you could change it if you wanted as long as the caliber listed on the stamp is the primary one for it. So I would assume that would apply to bbl's and uppers too. But I don't assume anything with the ATF. So I would try calling them first no luck with that you could right a letter ?
Maybe someone with more insite on the subject could help us