Can anyone give me some INFORMED advice (not just what you might think off the top of your head) about what would be the correct point of impact (i.e. ABOVE the 30 yard hold point) for a 30 yard sight-in range, if I want my Thompson Black Diamond Extended Range to be able to hit dead-on at 100 yards, IF I am using the open sights on the rifle which are fiber optic, red on front and 2 green dots on the back ? I have a great deal of experience in sighting in rifles that have scopes on them BUT I have practically zero experience with open sights on rifles. I am not going to have a scope on this rifle. I would be holding on the 30 yard sight-in target point with front red dot in horizontal alignment with the 2 back green dots (or at least the best I can hold them). Thanks.