1) valid gun
2) the bullets are stored in a magazine, not put into the barrel of the gun
3) fair enough
4a) domestic terrorism is not the same thing as murder
4b) I don't know if you know this but most large conventions have metal detectors and security guards and such so you can't just walk in with a f**king handgun, let alone an AK. You'd have to shoot from outside the convention center, in broad daylight.
4c) what -Tag- said