What reticle do you have in your scope? On your power adjustment ring you will notice one of the numbers has a mark on it that is the power you set it at to range with it. If you have a duplex, you can range pretty close with it but if you have mil hash marks you can get closer. Take your range finder and go to your range, range your targets at varying ranges, as you get out past 600 yards you may want to go with ranges like half of one hundred yards, mark your targets with 18-inch marks that you can see with your scope at the different ranges, or what-ever the average chest size is for the deer you are hunting. Set your scope on the number that has the triangular mark on it then look through the scope and count your hash marks writing them down in your range logbook. The 18 inches is the distance from the average man's chin to his waist band on him, but it is the average size of a buck mule deer's chest also this is how the military used to teach ranging with a scope. back when I learned it, they were pretty much fixed 10 power scopes. Leupold marks their power adjustment rings with a triangular mark for that reason, you never know when your batteries will die in your range finder especially, in cold snowy conditions if you aren't carrying it inside your coat. It's just a good back up in case something unexpected happens to your range finder, like snowy ground, batteries die, or it just isn't where you thought you put, because the kids or grandkids decided to use it and never thought to tell you or ask you if they could. Plan "B" just incase.