precision shooting & optics

[Yondering]

Can you provide a source for that? Or some math explanation how units don't matter. Cause I've never, never, never seen it.

Yes. The math is actually pretty simple: the measurement of a mil is simply a ratio of one "unit" per 1000 of the same "units". If we look at it in meters, we've got "meters per meter", or m/m. Those cancel each other out, and the 1/1000 is unitless; it's a universal ratio that describes a specific angle. Because it uses the same units on both sides of the fraction, it can be used in any measurement system (and it is).

For example, we know that one mil is equal to 3.6 inches per 100 yards, right? That's because 1 mil is 1 yard per 1,000 yards. Converting yards to inches, we have 36 inches per 1000 yards, or 3.6 inches per hundred yards. 0.1 mil is one tenth of that, or 0.36" per hundred yards. If we only measured things in yards and not inches, mils would be used exactly the same way in yards or meters, without the 36 in/yd conversion.

You are correct on the other uses for "mil" such as measuring thickness in machining or manufacturing meaning 1/1000 of an inch, and it's also present in words like "millimeter", meaning 1/1000 of a meter. When you look at the bigger picture, mil is simply a term that means 1/1000, and is not specific to a certain measurement system or type of units, even though it is more commonly used in the metric system.

Does that answer your question? I hope that wasn't too long-winded.

 

[Sunshine_Shooter]

BTW is there something in the water here lately? Seems like some guys just have a burning need to prove they're right by being rude to anyone they might disagree with.

I apologize for being rude. We're all trying to better ourselves and each other, but I was out of line. My bad.

I don't believe that I'm a step behind you in the linear vs angular units of measure.

Your assertion that a 'mil' is a unitless ratio is technically correct, but only because of how we define the term 'radian'. A radian is the radius of a circle, but measured on that circle's circumference. A milliradian is 1/1000th of that circle's radius, but on the circumference. Saying that a mil = 1 yard at 1,000 yards & a mil = 1m at 1,000m is correct, but that's because you're automatically cancelling out units. It is useful, I'll concede that point, but not that it is more useful than MOA for people who think in standard units. It's just as useful, no more and no less.

As to people who calculate drop in inches at yards, or really any 'length @ distance' format, are making it harder on themselves. If they would just use moa OR mils, they'd be better off.

 

[Yondering]

It is useful, I'll concede that point, but not that it is more useful than MOA for people who think in standard units. It's just as useful, no more and no less.

Apology accepted.

I don't recall saying that mils are more useful than MOA; we agree on all except this one point - mils are not exclusive to metric units. People who think in "standard units" like myself can use mils just as easily as those who prefer metric units. Personally I don't use metric units if I don't have to, regardless what I'm doing I'm still accustomed to inches, miles, gallons, etc, and using mils for shooting is no exception to that; all of my shooting measurements are in yards and inches.

 

[Sunshine_Shooter]

@Yondering Well, you got me reconsidering mrad v MoA. I sat down and did some calculating on paper and yeah, using mils seems unitless.