I shot mine with a 168 grain TSX at around 3200 fps. Never moved after the shot, but took a couple of minutes to die. When I shot my lion, he ate a 270 grain TSX at 2850 longitudinally through the heart. Took one leap, went down, and then died a couple of minutes later. He had a two inch hole through the heart and the bullet ended up in his hind leg.
What I learned from those two experiences is that cats are very susceptible to hydrostatic shock, and Barnes TSX's are probably too hard of a bullet to be ideal.
If I were to hunt leopard with a .308, would probably go with a 150 grain Ballistic Tip or SST pushed as fast as possible. That combo should help insure that your cat is laying dead at the bottom of the tree.
