I have never tried to set it with a custom dial. I run the numbers through a ballistics calculator and print out a cheat sheet. That way I can use the scope with more than one load and even move it to another rifle.
I have one on a 22 that I use to shoot out to 250 yards. I zeroed at 50 and had to use the old "trial and error" method to determine where to set the dials for various ranges between 50 and 250. I ran out of adjustment at 250.
