M*CARBO Brotherhood

What is Your Method for Measuring Scope Height?

I have a few techniques for measuring scope height for use in a range finder/ballistic calculator.

However, I’m curious. What does everyone else do to measure scope height of their scope above the bore?

For a follow-up question how far off the actual height do you think you can be until it shows a significant difference in the firing solution given by your range finder or ballistic calculator?


Welcome aboard!!
I am not a long range shooter to the point where I need such precise calculations, but am interested I hearing about it to expand my knowledge base.
What are your methods?


Cleaning rod method works for me.


Welcome to the farm! I use comfort.


Funny I just did this recently on my ar. First I divide the scope diameter by half, measure height of rings/mount (from lowest ring to where the mount sits on the rail) then measure and divide the barrel diameter by half (where it is flush with handguard) then measure from the top of the barrel to top of picatiny rail on handguard. Add them all up and you have your height over bore.

For bolt guns, I use a straight edge or long level and lightly clamp it onto the rings mounting surface. Measure end of barrel diameter and divide by half. Measure from the bottom tip of the barrel to bottom of level/straight edge. Then subtract the half of barrel diameter. Add ring height and half of scope tube diameter and you have your bore over height.

Sounds complicated, but it truly is easy. I use it for laser bore sighting software. I think there is also a company that makes a magnetic tool that sticks into the bore and you look through the scope to get the height over bore measurement. YMMV.


I always just measured from the center of the bore to the center of scope. I guess I’ve been doing it wrong all these years! ( funny thing, it seemed to work)