Bum-Bum-Buuummmmmmmm

CRACK! must have been the sound my poor airsoft gun made several months ago. We all knew the tip was broken, but until this morning, we didn't know that it didn't work without the tip. (EXPLANATION: I dreamed that Justin Bieber woke me up this morning, so I shot him with an airsoft gun. When I actually woke up, I amused myself by shooting my airsoft gun at different targets around the room. That's when I found out it didn't work) This is a picture of the gun before the damage was done:
Sad, isn't it? But now we are trying to figure out who did it! To help judge, click on this: https://spreadsheets.google.com/spreadsheet/viewform?formkey=dGR1YV9fZzQ2d1Z4YTNqMDBDd1BEbUE6MQ