Comment: I wondered about this as

I wondered about this as well. One of the reasons a .223 AR-15 is not a good home defense weapon is overpenetration of walls etc. Even in the Aurora shooting there were victims that were shot in the adjecent theater through the walls. Certainly in a school full of kids a couple rounds would have gone through a wall and grazed one or two without it necessarily being fatal. In all the supposed hundreds of rounds he fired, there were no injuries from overpenetration? For that matter, there were not even any shrapnel injuries from high-velocity rounds hitting wooden desks etc?

Im beginning to wonder if they had two empty classrooms that were enrolled with actors since the beginning of the year and the event was for the most part limited to these 2 rooms. That way, you dont need a whole school full of actors but just people that were in the affected rooms. They could have shot blanks or simply played sounds of the rifle going off and in the resulting panic the rest of the school assumed it was real.