I've taken several deer with 165 gr Barnes TSX in my .300WM. MV a bit over 3,000 fps. I am not convinced that they consistently open up on broadside heart/lung shots and switched back to lead bullets. This past season, my BIL took two deer with a 180 gr. TTSX out of his .30-06. MV about 300 fps slower than my TSX load and he had fantastic expansion on his broadside shots. The nose cavity is much larger on TTSX than on TSX. I will avoid TSX unless going for elk or bigger or unless I was intentionally going to shoot bone. I just bought a couple boxes of 150 gr TTSXs to work up a load for my .300WM because the 165 TSX was so accurate. I really want to hunt with Barnes bullets, but it has got to open fast enough. I plan to work up mono bullet loads for all of my hunting rifles. NY DEC wants hunters to transition away from lead, and knowing this state, it is just a matter of time before lead bullets are banned. I'd rather work on this at my leisure and then buy up a good stock of bullets.