Not very many people answered with go for the legs. I'd still go higher, go for the pelvis, and h ave a much larger target with the same results.
I don't think I've ever heard of anyone suggesting the bullet bounce before, but I've wiped out a lot of rodents that way, but it's because I'm never really certain about making that hit on a mouse, aiming low on the belly doubles the size of the kill zone
That's a very interesting idea, letting the ground absorb the explosion, sending most of the resulting force upward, leaving only a fraction going outward going laterally, and the inverse square effect will cut that out with every yard it travels.
Interesting to think about.