Keith - compared to other spitzer bullet designs, the TSX usually has the lowest ballistic coefficient - this is due to the air flow eddy producing bands. Any banded bullet has reduced BC, ie: increased drag over a similar shape that is smooth.

We just got used to nice high BC's with the smooth "X" bullets, then have these nice numbers reduced to 5/8's value was a shock.

Since the 300gr. Sierra BT has been toughened up in the jacket, it is probably the best for longer range Savana shooting than a much slower moving .416 bullet. Just a guess.

You can find the respective BC's by going to Barnes site.

Over 300 yards, there is probably nothing much to choose between them. Are you thinking about longer shooting?