As a rule of thumb the heavy bullets open slower, one bullet is not good for everything, I use the 250 either SW Gold Dot or XTP for deer they start out faster open faster and seem to be just right for deer, but for elk or bear or moose the 300 is better.
An exit hole on the far side is important for a blood trail beyond that the footpounds of energy spent on ground trees ect does not help bring the animal down sooner which is why the 240 or 250 or 260 is better suited to deer it spends most of its enegry in the deer and has just enough left to blow a nice hole for an exit for a blood trail. Lee