Please post your results...The whole principle is way over my head but I used it on my 22rf BR rifle and was AMAZED at the results.Fotheringill said:I have been a good boy and calculated Mr. Purdy's prescription twice. It is going to be cold tomorrow, but rifle and tuner all set up for the appropriate physical length. I know it will not be windless, but I NEED to go out and try it anyway.