Anyone who's pulled targets in military matches has seen bullets turn around in the sand bank butts and come back. Most of the energy is dissipated, though. I've fired 30-06 armor piercing and had the steel penetrator core come buzzing back overhead.
2015 BMW R9T, 2010 Ducati 1098 Streetfighter S
2009 Kaw 650 Versys, 1967 Triumph 650 TT Special