I agree with Charlie P on moving the targets without measuring. What I did for a friend who can't walk long distances was put him in a tree stand and take a 3D deer that I used and carry it to a possition for him to shoot. Then I'd retrieve his arrow and move the target to another possition. He got pretty good at hitting everything within 25 paces of his stand and he got a Muley while on stand in that same pinetree.