Bullet “skip” or ricochet is something you need to consider when you’re in an environment with heavy, solid structures or using such as cover from a bad guy in a public space.  In general, the harder and flatter a surface is, the more parallel to that surface a bullet will ricochet off. See what happens when bullets hit concrete and how that affects our defensive tactics.

More: http://www.personaldefensenetwork.com/video/004479_concrete-bullet-ricochet/