I have run through two nightforce, a SWFA, and three Bushnell LRTS.
Action is in a bell and Carlson with the AL chassis block and bedding around the lug and tang. 65inlbs, 35 and 50 have been tried.
Rail is bedded to the receiver.
Well optics and hardware is not the issue.
There are many factors in getting accuracy.
That's got to be real frustrating especially trying to work up loads. If there is a mechanical issue with the rifle there is no way you are going to correct by load development.
Even a factory rifle should get better groups with factory ammo.
How does factory ammo shoot?
Are you the original owner?
Did someone build this rifle?
How many rounds through it?
What action, trigger and barrel?
Is the barrel threaded?
Muzzle Brake?
Did you "Bore Scope" the barrel?
Could be the barrel among many things. If you have a good gunsmith in your area have them check the "Crown" and ID of the muzzle. I have heard of even some custom barrels not being finished correctly. I have cutback or just re-crowned barrels that were thought to be shot out and then started shooting cloverleafs.
We had a NEW Winchester Model 70 in 25WSSM. It shot 1"-2" groups out of the box with factory ammo. After the third box it opened up even more. Sent it back to now "Browning" since we bought the rifle right before the buyout from Winchester. Browning tested it and would not send it back to us. Said the rifle was unsafe and we had the option to get an "A" Bolt replacement or refund. Got a refund. So not all new rifles shoot correctly from the factory.
Good luck! Keep us updated on getting some good groups.