Long story short this is round 2 of issues that I have found doing this build between 2 different manufacturers rails.
First rail issue I ran into was a
USED Midwest Industries 15" FF rail system. When tightening the rail system, the rail canted to the side and didn't stay aligned with barrel using a mil spec PSA A3 Upper Receiver and my AAC .300Blkout barrel.
Second issue running trying different rail system with different upper receiver.
Now I get this problem with a
USED Daniel Defense 12.0 Lite rail using a mil spec BCM A3 Upper Receiver and my same AAC .300Blkout barrel.
I cant win! I did tighten the Daniel Defense AR15 Lite Rai barrel nut to 50 ft/lbs using the Daniel Defense AR15 Lite Rail barrel nut wrench and digital torque wrench. The plate behind the nut is loose as per instructions. I then installed the rail system and tightened the 6 socket head cap screws in order specified by instructions. Once they are tightened, you can see the cant between the barrel and the rail system.
You can look at the spacing between the barrel and rail to see that it is off. There's no way that I can ever maintain a zeros with my front sight, optic, 952V light or DBAL Laser unit at different distances due to issues with proper coalignment between rail and barrel.
Here's the setup..