Thanks for the info IG. I won't be using a new barrel or bolt, I am simply taking apart the OEM BCM components and putting them back together. The only thing changing is the handguard (replacing KAC RAS with DD) and the barrel nut but otherwise it should be good-to-go with the old gas tube. I already have to buy a couple tools to do this so that's 13 bucks saved by not having to buy a gas tube. Thanks again.

