I'm shooting a savage predator in .243. I have it zeroed out to 600 but would like to get it out to 800. When I sighted in out to 600 I just kept working my way back , 500, 525, 550,575, 600. Is it best to do it the same way or could I just sight in at 700 and 800 and then figure out the in between adjustments mathematically. Thanks for help.