I think it takes practice. Ive hit a couple bucks running and it is tough. Missed a few big ones too cause they were running. for me it isnt hard finding them in the scope its just the lead and all that and hitting them. i hit a coyote in the head at about 300 yards running full bore. that was intense. i double lunged a nice 4x4 this year, it was hit it the ass but it was still running really fast and i just killed it for him so we didnt have to go chase him. if i have to ill take running shots but if i think hes gonna stop soon ill let him stop