To duplicate the load(kind of a waste of time since every rifle shoots the same ammo differently.) you need to use the exact same components and the rifle that load was worked up for.
You can forget the off-the-lands stuff altogether as it's a different OAL for every rifle.
It's entirely unnecessary anyway. The whole off-the-lands thing is a load tweaking technique done, if you feel like it, after you've worked up the load. Finding the preferred distance off the lands in a 100% trial and error thing as well. There's no formula or standard distance.
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