zincwarrior stated the exact thing that to do as part of a self defense stratagy, RUN! If I get off enough shots 2-3 or whatever then I for one am getting away from the scene quickly.
Rifles, elevation, pyscho bent on murder, etc. is more than I am ready to take on. Let the trained swat team handle this. I want to protect myself in a real life, up close, shoot or die situation and I train myself for that. Part of my training is and has always been (due to where I live) to recognize danger, and steer clear. The bad guy may be yards away shooting toward me, but for me rather than shoot back, escape is the proper defense. Carrying a gun does not inspire me to want to be a hero or make me invicable or stupid,
Consider this 20 murders in 10 days, 19 by gun, 1 by knife, guess how many were more than 12 feet away, guess how many by a retreating bad guy. ZERO. Stuff happens, but 50 yards, not so much