I don't recall ever shooting anything other than the 140gr NBTs in front of a book max of IMR4350. The last time I chronoed them, I believe they were around 3250 FPS out of the 24" barrel.
The flat-shooting combo (at normal hunting distances) gave a bit of a cheat factor in the pre-rangefinder days.
The other positive for the combo was the relatively mild recoil.
