Lions do not have thick hides or large bones like a Cape buffalo. Bullets that are good enough for a large Canadian mule deer are all that is needed for a lion. A-frames or triple shocks are too sturdy for a lightly framed like a lion. A Speer 270 grain Hot-Cor probably will not open up on a broad side shot on a large lion.
Poor shooting is the biggest reason for bullet and\or caliber failures. Deer bullets are more than adequate for cats. That is lions or leopards.
