i have looked all over and cant find it. is there a search somewhere on this website? maybe im just blind. anyway, how do you calculate the true ballistic coeficient of a given bullet. i know theres given data for many bullets but ive heard that the bc changes for different conditions, velocity and rifles. also if you trim the meplate on a bullet such as the sierra matchking, the bc will change. can someone tell me a way to find the true bc of a given bullet. do you messure velocity at different ranges, or drop from one range to another? please help me out here. thanks in advance.