In Call of Duty: Modern Warfare, rapid firing a Barrett .50 caliber sniper rifle at extreme close range without looking down the scope.
A: "Holy shit! I just got .50 cal-ed from a yard away!"

B: (Man 1) "What are you doing wasting ammo?"

(Man 2) ".50 cal-ing this fool"

C: "HAHAHA, I just totally .50 cal-ed that camper FTW!"
by Desu! May 3, 2011
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