Source: http://www.youtube.com/watch?v=ZfnYWoffq-0&feature=BFa&list=SP48EBE6931EFDDB5F
^
These guys have so much good source material.
Got the idea and a friend of mine helped me out getting the Sniper to be a bit more realistic with the head bobbing. I gotta admit it does the trick.

KYR SP33DY, if you see this, keep doing what you're doing man, probably the funniest in the group next to Jahova's raging.