I just have a hard time blaming the bullets, I shoot BT's in the following
6mm PPC
6mm Rem.
7mm/08 (120 &140 gr.)
270 win.
25 WSSM
7 mm stw
now I use 55 gr in the PPC on deer no less, its a varmint bullet but the low velocity lets it penetrate pretty well, sometimes I don't get an exit but that's expected, I almost always get an exit with the 270 unless I hit them really hard at close range.
the 25 wssm I have never been able to recover a 115 gr BT on a deer, I've taken every angle shot I can think of, except a tx heart shot and have always gotten an exit, even on double shoulder shots. and I'm guessing I've taken 30 deer with them, and a few with the same rifle and 110 gr accubonds, the terminal performance between the 2 are identicle.
even the 7stw at 3550 fps, I will most of the time get an exit if I stay off the shoulder till the bullet hits around 3250 fps. I once shot a bear on the shoulder at 100 yards with it and at least a piece of the bullet exited. these are just my experiences with my rifles.
RR