5 shots might be enough for you to survive the event, but I doubt it would deescalate the event. My point is that shooting it out with the perps is a bad idea as it is likely to result in alot of colateral damage and may well get you killed. Once the shooting starts it will be fight or flight for the perps just as it is for everyone else, as soon as they showed up. Many of the perps may well fight, these kids are used to violence and even using violence, not always lethal violence, but violence. It is hard to imagine how a single person or several uncoordinated armed citizens could do anything but make the situation worse then it was.
"I'm what ya call a 'conscientious objector'; you know a coward".