@ga_trucklvr: yes it will be pinned and welded.
@quiet riot firearms: the miter mount requires 2.5 I believe but if the actual amount of barrel exposed is only 1.9 then it definitely will not work. I have a friend that has that can already and I was going to put it on there. Thanks for your input!
I am going to be purchasing this upper:
http://www.bravocompanyusa.com/BCM-14-5-Mid-Length-Upper-Receiver-Daniel-Defense-p/bcm-urg-mid-14%20ddl12.htm
I would like to purchase this flash hider to put on it:
http://www.advanced-armament.com/BLACKOUT-51T-Flash-Hider-MITER-Mount_p_448.html
It...