View Full Version : Weaver 20 moa base. Really 20 MOA?
Wildboarem
09-07-2013, 08:12 PM
I have a Weaver 20 MOA 1 piece base on my Stevens LA. I question whether it is 20 or some far less MOA base. To the naked eye it is fairly flat/level front to back. When measured with calipers there is only .04 difference front to back. Is that 20 MOA? I could spend a week trying to calculate it but was hoping someone had a 1 piece base laying around to confirm. I do have a 20 MOA on my WBY MKV, and you can't see the cant from across the room. Any help would be appreciated.
Distance between your measurements? LA Savage is ~7.5" long, 20 MOA is ~.0058" per inch. 7.5 X .0058 = ~.043...sounds about right depending on where you measured.
Wildboarem
09-07-2013, 11:50 PM
Between mounting holes so roughly 5.0"
Wildboarem
09-07-2013, 11:57 PM
Wouldn't 20 Moa be around .017 per inch? If that is that the case then my bases only has about 10 Moa, but like I said I need help and need to understand the math better.
thomae
09-10-2013, 10:36 AM
KRP is spot on.
Here's how to derive his answer:
reference: http://www.mathsisfun.com/sine-cosine-tangent.html
the tangent of an angle is = length of the opposite side / length of the adjacent side.
http://www.mathsisfun.com/algebra/images/trig-sin-cos-tan-divides.gif
Since we are discussing a slope (angle) of 20 minutes of angle, and there are 60 minutes in a degree, we know that this angle equals .33333o
So: Tan (.33333o)=opposite/1 inch
Using a calculator we find that Tan (.33333o)=0.0058178
So: for every 1 inch of length, a 20 minute of angle slope will rise (or fall) .005818 inches.
I love math in real life!!
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions Inc. All rights reserved.