Wow. . .So much to reply to.

First, like many hunters my father is a max PBR shooter. One zero for 0 - max range. That is a choice he has made and we might all be wise to look into these simple ideas. One zero requires that a bullet have a reasonably high BC(~.500 or higher), good killing performance and ahigh velocity. The 270 WSM puts them out there fast. Slowing down is contradictory to my Father's end goal. He has killed a lot of deer. . .I trust he knows something about all of this.

Also, we use SST's, ballistic tips, HP's, or flat point tips because in the magazine of a standard weight 270 WSM the bullet tips deform. While this doesn't cause them to go sideways, it does cause inaccuracy. The other tips do not have this problem.

Thank you for the resonses about the various bonded bullets you have had good or not so good luck with. It looks like the Barnes TSX and Nosler Accubond are kind of in a dead heat as far as responses are going. Any idea on the BC for either? Also, Woodleigh makes a 150gr hunting bullet which I think is a bonded core. Any experience with these?

Last, my father and I are not lazy by not doing penetration tests. . .We do not have a test deer we can shoot over and over which comes back to life everytime. That is why we are asking you. If you shoot geletain or wet phone books or something, great. Tell me your results. BTW. . .How many wet phone books does it take to simulate an Elk or Antelope? I say this in jest. My point is that no penetration test is much more than a slightly usable comparison guide. We choose to use performance on game, why, because it WORKS. Since we are not talking about performance on people, I see no reason to guess with some other medium than game animals. And no, there are not any game animals running around with a bullet in them that we guessed wrong on. We shoot them twice if needed.