The guy that shot him was a 25 year old ex marine who suffers from Post Traumatic Stress Disorder.
I have heard that too, however, I have also heard that the guy that Kyle was trying to help was ex military suffering from PTSD and was a neighbor of the shooter!
Sad situation indeed. Rather odd to have a person suffering from PTSD at a gun range. Even I know when disarming a bomb you don’t hand the cutters to the guy with the shakiest hands.