In my quest for suitable round for my AR, I am diving into the uncharted waters of the infamous OAL/seating depth guage. But which comes first? Do you experiment with various powder charges then various OAL depths using a seating guage...or Do I adjust the seating depth first, maybe .15 to start then experiment with powder loads. I am using a Hornady seating depth/OAL guage & a Hornady comparator if that eases your minds. I will measuring at the ogive.