I was doing some research regarding the actual MOA gained when using Burris Signature Zee rings and came across quite a bit of good information. I've tried to compile the nexus of my research. I want to thank everyone who helped me out in this effort. Please feel free to make contributions and corrections as needed. (ps, be gentle, this is my first endeavor!

)

Hope this helps some of ya'll, Doc

**Determining Actual MOA When Using Burris Signature Zee Rings**
__Method 1- Using 100 yd. shift method:__*

> Formula:

*[( Total Offset / Ring Spacing) x 3600] / 1.047 = MOA @ 100 yds*
-Total Ring Offset = Total of Ring Insert Dimension (e.g. Using 0.010 inserts = 0.010 + 0.010 = 0.20)

-Ring Spacing = Distance rings are spaced apart in inches (measured to 0.001 inches)

-3600 = Inches in 100 yds

-1.047 = inches per MOA

+Example:

>Using 30mm Burris Signature Zee Rings w/0.010 ring inserts

Total Ring Offset = 0.010 + 0.010 = 0.020

Ring Spacing = 3.546 (picatinny standard rail slot spacing = 0.394, 10 picatinny slots = 3.940, therefore 9 picatinny slots = 3.546)

[(0.020 / 3.546) x 3600] / 1.047 = MOA

[(005640157) x 3600] / 1.047 = MOA

[20.3045652] / 1.047 = MOA

19.393089 = MOA

Therefore using 30mm Burris Signature Zee Rings, MOA gain using standard picatinny rail is:

21.7 MOA @ 3.152 spacing ( 8 standard picatinny slot spacing)

19.3 MOA @ 3.546 spacing ( 9 standard picatinny slot spacing)

17.4 MOA @ 3.940 spacing (10 standard picatinny slot spacing)

__Method 2 Using arc tan Method:__**

> Formula:

*Arc tan ( A / B ) / 0.0167 = MOA*
-A = Total Ring Offset = Total of Ring Insert Dimension (e.g. Using 0.010 inserts = 0.010 + 0.010 = 0.20)

-B = Ring Spacing = Distance rings are spaced apart in inches (measured to 0.001 inches)

-0.0167 deg (or 1/60 degree equivalent to 1 MOA)

-Arc tan = arc of the tangent

+Example:

>Using 30mm Burris Signature Zee Rings w/0.010 ring inserts

Total Ring Offset = 0.010 + 0.010 = 0.020

Ring Spacing = 3.546 (picatinny standard rail slot spacing = 0.394, 10 picatinny slots = 3.940, therefore 9 picatinny slots = 3.546)

Arc tan (0.020 / 3.546) / 0.0167 = MOA

Arc tan (0.005640157) / 0.0167 = MOA

* Using a scientific calculator: (0.00560157 {inv tan}) to obtain arc tan result = (0.323153818)

0.323153818 / 0.0167 = MOA

19.3505 = MOA

Therefore using 30mm Burris Signature Zee Rings, MOA gain using standard picatinny rail is:

21.7 MOA @ 3.152 spacing ( 8 standard picatinny slot spacing)

19.3 MOA @ 3.546 spacing ( 9 standard picatinny slot spacing)

17.4 MOA @ 3.940 spacing (10 standard picatinny slot spacing)

As is evident, the further apart your Burris Signature Zee Rings are the less MOA advantage you will obtain. If you are using 1inch Burris Signature Zee Rings two counter opposed 0.020 inserts might be recommended to obtain 20 MOA with greater ring spacing.

I utilize the 30mm Burris Signature Zee Rings with the 0.010 inserts because they, along with 0.00 inserts, are the only inserts currently supplied. Therefore to obtain a 20 MOA advantage a closer ring spacing of 3.152 inches or 3.546 inches must be used. Apparently, I assume, this closer ring spacing is the reason Burris has beefed up the 30mm rings when compared to the 1inch rings.

When using Burris Signature Zee Rings always ensure the inserts are opposed, with the fat insert on the bottom in the rear ring, and fat insert on top in the front ring. This lifts the rear and lowers the front of the scope to obtain increased MOA and increased scope area.

*extracted from Elevation Shift with Burris Sig Rings within AccurateShooter.com

**found in LongRangeHunting.com online magazine forum. I wrote down the formula but cant find the thread to reference. My Bad.