As any trained firearm user knows, it is vital when using a defensive weapon that you be fully aware of how it works and what the consequences are should you miss your target. Rob Pincus discusses some of the results that you might encounter if you misfire in a close-quarters incident, including what will happen if they are fired into intermediate barriers and deflect through standard drywall hallways into rooms. He talks about the specs of some of the firearms and their ammunition that you may encounter on firing ranges or in real-world applications, and then puts them to the test to show you how they’re affected by the walls in a typical Western drywall home and the tempered glass in a standard double-pane window or door. By looking at the size of the bullet holes, their expansion and the amount of deflection or deviation, you can roughly determine how dangerous the rounds in your particular weapon might be if you misfire.