I've had very good luck using the 168 TSX BT in a NULA .308 on a couple of Colorado bulls, one at 266 yards, the other at 319 yards. I would have preferred a 150 Barnes but the 168 shot so accurately, I stuck with it. Muzzle velocity was 2,700 fps, about the most one can expect with a 22" barrel and H4895. I could get slightly more speed with Varget, but not better accuracy. I'm pretty sure you could get at least another 100 fps from this bullet in an '06.