www.ammoland.com
Schizophrenia in particular is definitely tough, especially if undiagnosed. My high school girlfriend had a quiet but seemingly normal brother (early 20's). Nobody expected him of having mental illness, until the morning he shot a crossbow at an imaginary assailant, through their front window and into the siding of the house across the street. When he was at the hospital, they searched his room and had been stockpiling all sorts of oddball weaponry (this was in CT, so I don't recall any of them being firearms). His schizophrenia was bad enough that I never saw him again during my junior and senior years of school - he was institutionalized that entire time.
You almost have to let the victim get seriously injured before intervening so that even if they say “why did you do that?! He wasn’t going to really hurt me!”, any reasonable person would see that “he broke your orbital bone and gave you a concussion, that’s pretty serious.”
