FWIW, a while back I used the ballistic calculator in my PACT chronograph to compare trajectories of some "light for caliber" TTSXs with more traditional weight Partitions and Ballistic Tips in .277 and .308 calibers. While this suggested nothing about penetration, it did suggest that the trajectories were not that different out to 500 yards despite the fact that the muzzle velocities used for the TTSXs were 10-15% higher.
