A One Hundred Round Drum

A 100-round drum for the AR-15 Assault Rifle 
AR-15 with scope and 100-round drum (this is not the weapon used in the Colorado attacks)

I have to admit--I did not know you could legally purchase a 100-round drum for the AR-15 assault rifle, which is a knockoff of the M16.  the civilian version of the M16.

When I used the M16A2 rifle, the largest clip we were issued was a thirty round clip. This would get you through a range qualification and that was the extent of my experience.

Seriously--James Holmes had a 100-round drum and had purchased 3,000 rounds? And we still can't have a discussion about gun control, ever?

What a crazy world.