Sights above bore line? How do I...

[M Gruber]

Bought 1000 rounds of 308 168 grain Federal Gold Medal Match. On the box there is a ballistics table. The info provided is based on a 600 yard zero with the sights 1.5" above the bore line.

My question is this.......how is the 1.5" above the bore line measured?
From what point to what point?

M Gruber

[DAVID NANCARROW]

It is the distance between the center of the bore and the center of the scope lens. To figure, I mike the barrel diameter under the front of the scope and divide by two, mike the scope bell diameter and divide by 2, and add the distance between the top of the barrel surface to the bottom of the scope bell.

[M Gruber]

thanks..........
I'll give that a try.