On Sun, 16 Nov 2008 08:18:39 -0800 (PST), Frogwatch
wrote:

Although a bullet will bounce at a shallow angle from water or sand, I
doubt it is possible for a 180 degree bounce to happen. OK, it is
"possible" but it is probably more likely you will get hit by a
meteorite twice.

Think corner reflector, it takes a double bounce from a 90 degree
angle.