If a new rifle is only good for a minute of angle at best and one fires a ladder test at 400 yards, how does one know any bullet hole is at the top or the bottom of the rifle's group ?
It's a fairly complex concept, but I like to explain it like this:
1) You note where the bullet hits the target.
2) If the other rounds hit below it, it's at the top of the group.
Now here's the tricky part:
3) And vice-versa.
