RE: OCL vs Ogive
I also use a black marker but I take a unsized case and put a small flat spot in it by just pushing the side of the case against my bench, just enough to make the bullet a little snug. Then I black the bullet out with the markerand place it in the chamber and close the bolt. I then take it out of the chamber and carefully pull the bulet back out until I see where it stopped in the blacked out part. I put the bullet back in just to where the line in the blacked out part is and then measure the Ogive and that is my OAL unless they won't cycle in my magazine then I start seating deeper until they just barely will cycle in my magazine. I do this 3-5 times to make sure I get a good consistant measurement.