I guess I will be odd man out as I think MOA/MOA is decided superior to MILs in a hunting optic.
1 MOA is a better �size� to work with for shooting. A MIL is too large and, when working wind, even reticles such as Leupold's TMR with � MIL hashes, is courser than I prefer. Working in � MOA increments on wind holds supplies all the precision I can use from field shooting positions and allows me to get my focus off the reticle and on the target.
MOA is pretty much the universal unit of measurement for rifle accuracy (in the USA) and even the guys who are dedicated to MILs usually discuss groups size or hit potential in MOA or the approximation inches at 100yds. Because we use the US customary units for linear measurements MILS has a hard time translating to accuracy standards or hit potential. So if you go to MILS you will still use MOA. Why use 2 systems?
Being able to determine linear measurements in inches is very useful if you wish to check a buck antler spread or tine length. MOA is quite a bit faster and simpler to work with if you are using yards for distance and inches for measurements. I am not sure what the minimums for B&C alltime are in centimeters.
MOA works better for quick wind drift formulas. As an example my 243 Win/105gr VLD @ my standard density (85%) has a Range / 2 = MOA drift in 10mph crosswind. This is an approximation but holds very close.
Example:
10 mph drift at 500yds is approximately 2.5 MOA
10 mph drift at 1000yds is approximately 5.0 MOA
My .264 Win Mag/ 140gr VLD @ 3250fps @ my standard density uses the same formula but is modified by subtracting 1 MOA from the Range / 2 formula.
Example:
10 mph drift at 500yds is approximately 1.5 MOA
10 mph drift at 1000yds is approximately 4.0 MOA
Wind drift has a tendency to work out in a linear manner as far as MOA holds.
I believe it is easier for a spotter to give MOA corrections than MIL corrections when using non reticle equipped spotting scope. Most all of us do not use a spotting scope with a reticle. When I am looking at a buck 800yds away I can �see� MOA easily because his back to brisket is 2.5 MOA. His back to brisket is also .7 MILs but it is much clumsier as nothing in the shooters reticle is exactly or easily broken down into a .7 increment.
Matching reticle to adjustments makes sense and there are more options in MIL/MIL but that is changing.
Short answer is if you are used to US customary units for range and measurements then MOA has a lot to offer.
Back in the day of being a Fire Suport Man (enlisted FO) we used mils to calculate deviation corrections to the observed fall of shot in relation to the target.
Our binos had a reticle with an index every 10 mils. In practice, we rounded distance from observer to target to the nearest 1000 meters, then used that factor to multiply by the measured deviation in mils, to determine a correction in meters we would send back to the FDC.
For example, target 2800 meters from observer gets an O-T factor of 3. An impact observed 20 mils left of target, would be multiplied by 3, for a correction of "Right Six Zero" (60 meters)
Our compasses had a mil and degree index. A full circle had 6400 mils.
Here's the part where it goes to hell, a circle with a radius of 1000 meters, has a circumference of something like 6283 meters....
Shane,
You hit one issue with MILs, as a MIL is not always a MIL. In real mathematics there are 6283.185 (2 X pie X 1000) Milradians in a circle. The US military rounded to 6400 to make the arty calculations simpler. Other countries rounded to 6300 or even 6000 (damn Russkies).
Some ballistic programs, when computing the bore angle, use real calculus radians and some use the 6400 approximation. This also applies to scope manufacturing concerning reticle subtension and click values.
