You're going to get more than one way to do this, because individuals have different scopes/irons, different needs, skill levels... you get the idea.
I will, as a general rule, set BUS to zero at 50 yds with a 55 gr. bullet. With this setting, other than at the muzzle, you'll never be more than 2" above or below your POA out to 270 yds.
Scope? Hard to say. You don't say what you have for a reticle... the functionality of the reticle tends to establish your best zero.
Shoulder Drive Nicholson Club