For a straight F/TR rig, I would look at the 190VLD's or 208AMAX's loaded loooonnng. With a 30" barrel should get good velocity and minimizing wind drift is more important than how flat it shoot on a KD range.
Pick the bullet you want to shoot, load up some dummy rounds, send them to Dave Kiff and PT&G to have a reamer cut for it. Or he might very possibly have a reamer print already with a long throat for the heavies.
Palma95 reamer has a short throat, for 155 to 175's.
my two cents im no expert. Choosing your bullet brass, and oal loading a dummy and having dave kiff turn a reamer where the bullet kisses the lands is a great way to go! i ve done it many times. If you want to sell the reamer youll only be out a penny or two The past ten years ive used gre-tan and also provide greg with a dummy. Greg has a lot of reamers but they have no throats- he selects the one he has with the neck desired. He cuts the throat seperatly for kiss the lands on the dummy. This is not quite as precise as blueprinting a reamer to a dummy via kiff but its pretty damn close and saves the cost of a reamer.
IMHO this is better than selecting any stock reamer that is not matched to a dummy, not that that method will yield bad results!
I like the 155s seated way out but ive never shot the heavys. My perception is he 155 scenars at 3000 fps out of a 28' show just a little bit more drift than a 140 6.5 amax at 2800 at 1000 yards. 24.r minutes elevation off a 100 zero at raton. They are noticably better than the 175smk IMHO. But a 11.25 works well for the 155 scenars so if you chose that you could try the 155s the 175s and the 178's. I dont know if a 11.25 is fast enough for the heavys.