I use MPBR at an 6" target. Most prople seem to use an 8" target. If you don't know what that relates to, ask. I'll need the cartridge and listed velocity. From there I can fake enough to give you a trajectory chart as far as you want. Most guy's seem to think 400 yds is far enough, how about to there. Do you want 25 or 50 yard increment's? As I will have to fake some numbers, you'll have to go out and test fire. But sight in first at say 100yds and find the ammo that shoot's best in your rifle.
How you sight in depends upon what cartridge you are using and the conditions that you hunt. For example, it would not make sense to zero a 30-30 at 200 yds or if you hunt thick cover where 75 yds is a long shot. Most of us use cartridges that are capable of long range killing power, so something like a 200 yd zero is a good general choice. I have a buddy that zeros his 300 Weatherby Mag at 400 yds, but he hunts Mule Deer and Antelope in the wide open West. I personally would not want to take a shot at that distance becasue I have no access to a range with those distances to practice.
i agree that a lot depends on the rifle's purpose for sighting in a scope. my 7mm-08, .30-06, and .300 mag are zeroed at 200 yards. my .375 h&h and .376 are zeroed at 100 yards. my .458 is zeroed at 50 yards (no scope-haha). i may have to rezero the .300 for leopard hunting next month since i doubt i will take such a long shot.
Boy I don't know about the mpmbr or whatever. I'm not sure if you'll need the 8 inch or the 6 inch or the milk jug with a sticker on it, best by far. I prefer the 10 inch target, about 10 inches of rockchuck.
What does "gauge" mean anyway? As used here gauge means the number of round lead balls the same diameter as the inside of the barrel (aka the bore) that it would take to weigh one pound. It takes 12 lead balls the same diameter as a 12 gauge barrel to weigh a pound. The smaller 20 gauge would require 20 balls of that barrel diameter. The larger bore 12 gauge would require 12 lead balls of the bore diameter to weigh one pound.
In general the number of pellets in a shotgun shell...