Well, that stat was completely made up by you. Especially with anemic handgun rounds people can take a lot of shots before they flee or go down, depending on caliber, motivation of the attacker, what drugs are in their bloodstream, and the anatomical significance of the shots (or them being on target at all.) There’s plenty of videos that show people taking 10+ rounds before they stop attacking. The actual stat is that civilians (unlike police) are unlikely to reload in defensive encounters and so do fire less but it still may need to be more than 6 in many cases. (The reason may surprise you: Civilians, unlike the police, are actually responsible for what their rounds strike. The police don’t have to give a fuck, citizens do.)