perhaps its antilagg its supposed to even out the playing field..
ANTI-LAG Definition and Explanation:Its a latency-based system which uses algorithms to adjust hit registrations according to a mean average between 2 players whose latency (ping) is plus/minus 50 difference between them. It will delay the rigistration for faster connections, and speed it up for the slower one. In practice, in speeding up the registration, this sometimes appears like you've been hit before the player has even taken a shot. But that is only an illusion created by the algorithm used.Between players whose latency (ping) is not greater than a certain mean average between them, no noticable delay or speeding up is made. In other words, it gives slower ping players a fighting chance against players with a much faster ping. But between players whose ping is roughly the same, no such adjustments are made.If server admins want to reduce the amount of compensation used when anti-lag is enabled (and, it has to be said, many game industry insiders insist that anti-lag is by far and away the "fairer" system), make sure you exclude players with a ping greater than 50/60 the average player ping on your server.
international players on same server and this occurs -those one bar players are compensated for there poor connection so we can play nice together
this is how cod4 antilagg works im guessing cod5 too