I built a 6.5 STW for a customer a few years back with a fluted 30" PAC-NOR barrel. He shoots the hornady 140 AMAX @ 3500 fps. If you are interested I could get you an email address and you can get info on the project from the horses mouth. I do know he has anchored a couple of deer with it.
The guy's name is Jim Kramer. He is a total gun guy. His email is firstname.lastname@example.org
Just tell him where you got his email from and I am sure he will answer any questions you might have. Tell him I said hi.