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Determining Correct Scope Base Angle
Returning to my earlier question of how thick of a shim do I need under my rear scope base to get the desired MOA correction? First we need to measure the distance center to center of our scope bases. On my example gun the dimension is 4.75 inches. 4.75 inches is the radius we use to work out the same problem that we worked above.

scope base angle
This picture shows the three .010” thick brass shims I used.

4.75 x 2 x 3.1416 = 29.85

29.85 / 360 = .083

.083 / 60 = .0014 which equals one MOA at 4.75 inches, but I need 30 MOA.

.0014 x 30 = .042 inches or 42 thousands of an inch.

scope base angle
This picture shows the receiver masked off ready to epoxy everything together.

So a shim .042 thousands of and inch under the rear base will give me 30 MOA of correction and get my elevation adjustments for shooting out to 1000 yards centered in my scope’s adjustment range.

scope base angle
This picture shows the height difference of the bases after shimming.

In the end I only used .030” of shim because some of my correction was being done by the Burris offset inserts. With everything cleaned and JB welded together I’m confident nothing will move and I can easily crank in all the elevation I will need without being near the end of my adjustments.

scope base angle
This picture shows the Burris Signature Zee rings assembled.

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