I wonder how Google will rank that question. Anyway, many members of TTAG’s Armed Intelligentsia worry that their self-defense bullet or bullets might not stop inside the bad guy. For good reason? Here’s a defensive gun use from this morning’s miamiherald.com. “Arellano and his two brothers tried to stop the man [threatening them with a wood plank]. The wife and 3-year-old son managed to get in the car, but the 5-year-old daughter could not, [spokeswoman] Coleman-Wright said. Arellano said he was going to call the police. ‘And that’s when the guy lost it, became very agitated and made aggression toward [Arellano’s] daughter,’ Coleman-Wright said. Arellano fired once, fatally hitting the man in the chest. The same bullet hit Arellano’s brother, who was expected to recover.” So it does happen. Do penetration issues determine your choice of firearm, caliber, type of ammo and training?