I've always wondered why not skip the formalities and just go for the head. That way, if it's a nutjob with a bullet resistant vest, well you bypass it automatically. Keep the chest shots only for when you have to hip shoot.
Always practice head shots if you use your sights. No two this, one that or whatever. Chest if hip/retention shooting.
"The government has confiscated all of our rights and is selling them back to us in the form of permits."