• Watch Out for Scammers!

    We've now added a color code for all accounts. Orange accounts are new members, Blue are full members, and Green are Supporters. If you get a message about a sale from an orange account, make sure you pay attention before sending any money!

How to measure scope over bore

m1a convert

Sergeant
Full Member
Minuteman
Mar 29, 2003
287
4
Idaho Falls
I see in ballistic programs it asks for the scopes height over the bore.

What is the easiest, most accurate way to measure this?
 
Re: How to measure scope over bore

Diameter of the action, divided by two = A.
Diameter of the scope tube, divided by two = B.
Gap between scope & action = C.

A + B + C = distance between bore axis and scope axis, or "scope height over bore".

Using this method, we can get within a few thousandths, but that is more precise than we actually need.

If you look at some ballistics charts run with some variation in this number, you'll note that within 1/4" is close enough for most applications. Most folks can eyeball within 1/4" just holding a scale or rule against the side of the rifle.....
 
Re: How to measure scope over bore

As Ed notes, if you experiment with a ballistics program, you'll find that changes of a quarter inch make little appreciable difference to the program output.

So, keep it simple, and just use a ruler or a tape measure.
 
Re: How to measure scope over bore

Take a ruler or caliper and do it like the pictures below. No need for calculus to figure it out.
P6120518.jpg

P6120517.jpg
 
Re: How to measure scope over bore

How could it get any easier than the way Rob does it?

Keith
 
Re: How to measure scope over bore

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: KS</div><div class="ubbcode-body">How could it get any easier than the way Rob does it?</div></div>Have someone else do it.