I appreciate everyones advice but I think I have found out what's going to work the best a 4 by 8 sheet of plywood with a bullseye at the top shoot at 100 back up to 2 measure the distance back up to three measure the distance back up to four measure the distance make my own drop chart and forget this stupid ballistics calculator.the only way to learn how to do it is to get off the couch and go out and do it