Re: Converting MOA to MIL
If field shooting & spotting, quick math is more important than perfect conversion to beat wind change. Try the basis of:
MOA * 3 / 10
You would be able to quickly convert:
1 MOA = 0.3 mil
2 MOA = 0.6 mil
3 MOA = 0.9 mil
etc
Next, get used to spotting in 1/3 MOA increments (vs 1/4 MOA) where every 1/3 MOA = 0.1 mil, which is what his turrets are in. Consider...if you read a 1/2 MOA adjustment, and give your shooter a 0.15 mil correction, he will probably say wtf cause he wants to hear 0.1 or 0.2 -- giving him 0.15 mil would be like you receiving an in-between correction like 0.375 MOA.
This will give you the fastest field math. Quick illustration:
4.33 MOA = 1.3 Mil --> 4*3 + 1 = 13 / 10 = 1.3
7.66 MOA = 2.3 Mil --> 7*3 + 2 = 23 / 10 = 2.3
0.66 MOA = 0.2 Mil
Actual error? If you take 7.66 MOA above, actual conversion is:
7.66 / 3.438 = 2.228 Mil
You gave 2.3 mil
Error = 0.072 mil * 3.6 = 0.26" error per 100 yards
At 500 yards, that's a 1.3" error for a 40.1" adjustment -- I'll take that. All that is also assuming he didn't pull his shot and you read the impact correctly.
If you have time to do intricate calculations, read wind change and deliver the proper correction, I would love to learn that trick!