You see, none of these things happened, because UT Austin has a no firearms policy.
The following weapons are prohibited:
Chemical dispensing devices
Club or night stick,
I dunno - maybe Colton got confused that they mentioned both firearms and machine guns - perhaps an assault rifle is neither, and therefore allowed? Maybe he figured his ammunition was ok because it wasn't armor piercing.
Surely, Colton never ever ever would have violated law or school policy. That's why we have laws and policies, right?