I never really got into bow hunting. Rifles seem to work just fine for zombies and animals, and I just don't see myself going all "Daryl" with a crossbow either. The Rac Em Bac company has recently created the ultimate arrow in zombie hunting stopping capability; it is tipped with a .357 or .38 special. Check out the vid below:
Although this looks a little strange, it seems to pack quite a punch. At $40 for a six pack this is a little pricey, but would be pretty good for wild boar or other "nuisance" animals.