They don't/can't explode. They are pure copper. We use a very soft copper so that they deform very rapidly on impact. They open with a few petals like a banana. They are designed to shed those petals. This rapid expansion and petal shedding creates the shock that is very impressive. The 70% to 90% retained (depending on the chosen bullet) weight will have a square flat front designed for deep straight line penetration. This retained weight needs to keep velocity after impact. Bullets that stop inside an animal stop doing damage. They don't have brakes, they slow down until they stop, doing less and less damage as they come to a stop. There is no such thing as energy dump. There is such a thing as shock and permanent wound channel. If we have a bullet that owns but does not shed its petals, we almost consider it a bullet failure. The shed petals very often follow the retained shank for computer pass through as well. Like 3 or 4 little 20g bullets.
Explode- no. Rapid expansion shedding a few pieces with the same weight retention regardless of impact vel- yes.