Re: Coal or ogive
Bullet tips can vary considerably, so that OAL measurements will always be inaccurate. Its OK to check them from a reloading manual, but use them only as a guide.
Measuring from the case bottom to ogive start is much better and more accurate. Get a Hornady OAL guage and read the instructions. You need to find the bullet depth where you can first see the rifling on bullet, then move back from there. Do this with a dummy round (no powder or primer). If your bullets touch the lands, you might try to extract a loaded round and find the bullet stuck in the bore, and powder thru the action. Not good when you are on a hunting trip.