The common thing in most of these shootings though is always, "I never expected this, he always seemed okay, etc." from the shooter's friends/families/acquaintances. That aside, it's not as difficult to buy parts and build the gun yourself, borrow someone's, etc. As long as there are guns, there will be gun crimes. This person is murdering children and his parents, he won't give two hoots how hard it is to get a gun. He's going to get it if he wants, he has nothing to lose. The delay in acquiring a gun isn't going to give them time to just 'get over it' which isn't how mental disorders work, lol.
I still stand by my aforementioned statistic that if a civilian, or in this case a schoolteacher or security guard, were armed then this tragedy could have been stopped early in its tracks.