Well you have to lead the deer properly according to wind and distance and how fast its moving as well as the type of deer. I find that whitetails will tend to run in a normal fashion so it easier to lead them but mule deer dont really run they hop along like a rabbit so they are really hard to hit right with a running shot(i know i dont take running shots on mule deer) butwhitetails if they are running and i thinks its a shot i can make i will take it.