mrad and moa

[M-61]

I wonder what percentage of the people who have or are contemplating buying a scope that has either a reticle that has ranging and hold off markings in radians, and or scope turrets with milliradian divisions, could explain what a radian is, or how the calculation is done to range distance using those marks, or know that neither has anything to do with the metric system, or the military.

The percentage will be horribly low. Unnecessarily so, in my opinion, due to folks thinking it is part of the metric system or it has to do with the military and therefore should be better. Nothing like seeing "MILSPEC" after something, which seems to have the connotation 'it must be better'. Not realizing that a particular Military Specification may date back to the 40's or 50's.
Once you get past METRIC and MILITARY and realize it has nothing to with either, one can learn what it really is. But I go back to my earlier comment that I just don't the need for this change. I must be missing something in this other than a marketing ploy.

 

[Eric Leonard]

as long as the reticle and the clix match I can use either just as well but still prefer MOA/MOA clix/reticle in FFP for a tactical/PRS type rifle and in SFP for a target rifle,,

as long as when I see moa`s in my reticle and can make moa clix on the knobs I am happy,,

 

[Jammer Six]

Sailors, surveyors, engineers and most physical scientists will be able to tell you more about mils than you want to know. Most of them (with the exception of the surveyors) would laugh at the idea of using degrees.

It's possible to serve twenty years without running into a mil.

 

[Jammer Six]

It's been pointed out to me by She Who Points Things Out that my point was not clear.

My point was that mils are purely a matter of education, not experience.

When one is nailing a house together, one starts off with a hammer and a pile of nails. One hits one's thumb. Not once, but many times. However, by the time one finishes the first house (well, usually. Johnny could be special.) one understands how to drive a nail. (One may not be good at it, or fast, but one should have a grasp of the basics of the process.) That is learning through experience.

However, no matter how many times one deals with mils, or uses mils to measure angles or distance, one will never figure out the definition of what a mil is unless it is taught to him. The definition of what a mil is is only passed on by pure, theoretical education. Moving the strike of a mortar or a bullet won't do it. (These theories ignore the folks who figured the first mil out. I don't know which way they worked, whether they worked backwards from the result or forwards from the definition.)

That is the difference between learning through education and learning through experience.

At one time, I thought that one was a skill and the other knowledge, but She Who Dispels Myths And Corrects The Wrong corrected me.

 

[icu812]

Guys get hung up on inches or cenimeters and neither one really matters. If you have a quality optic with matching turrets/reticle, quit thinking in linear measurments. All you need to focus on is how far your impact was away from your POA and use your reticle as a measuring stick then dial accordingly. MOA or MILS it works the same. Just remember SFP scopes would need to be on the correct power for the reticle subtensions to be correct. That's why so many guys are going to FFP optics, the reticle can be used for corrections at any power.

 

[Jammer Six]

There it is!

Use the optic itself to measure the correction, dial in the correction, done.

(That's also a strong argument for fixed power scopes. Which is what I did.)

 

[snakepit]

It really depends on the calibration the MRAD scope is using as to how many clicks it takes to move about 1 inch at 100 yards. On the Sightron MRAD 10-50x60 scope I have each click is 0.05MRAD which is 0.18" at 100 yards so 6 clicks would be 1.08 inches at 100 yds. The top of the Sightron MRAD adjustment turret (which is a large tactical knob) actually has the figures indicated on it. It says one click is 0.05 MRAD 0.18in/100yds and 0.5 CM/100m. This makes it close to half way between a 1/8 and 1/4 inch click scope.

 

[CharlieNC]

I wonder what percentage of the people who have or are contemplating buying a scope that has either a reticle that has ranging and hold off markings in radians, and or scope turrets with milliradian divisions, could explain what a radian is, or how the calculation is done to range distance using those marks, or know that neither has anything to do with the metric system, or the military.

Like M61 noted a mil radian subtens 1/1000 of the distance, so like the metric system it is simply powers of 10. Actually simpler to understand and use than 1.047in moa. If you recall the circumference of a circle is C=2pi R. Similarly the arc length subtended by the angle Th is S=RxTh, where the angle Th is measured in radians (not in degrees). From the definition of the circumference (C above) it follows that there are 2pi radians in a circle, which is equivalent to 360 degrees. So knowing the size of an object in your reticle, and the 1/1000 relationship for a mil, the calculation for range is straightforward.

 

[brian427cobra]

MOA and MRAD work exactly the same if the end user does not give either a hard value, do not buy a scope with a MRAD reticle and MOA knobs, lastly pick the right tool for the job, fixed static position shooting at known distances a MOA scope is a better scope, shooting fast from variable positions at various distances and\or moving targets a MRAD scope is a better tool.

 

[XTR]

The only place I use MOA turrets is on my target scopes because NRA targets are laid out in approximate MOA rings, so moving from the middle of the 9 ring to the middle of the X ring is 3/4 MOA and I know how far to turn the knob. I'm looking at a measurement that is directly convertible to MOA or fractions thereof.

In my hunting and tactical scopes I want and use mils. Using a base 10 system is way easier than a base 6 one. The reticles and the turrets match and everything is easy.

Look again at the graphic at the 13th post on this thread.

 

[alf]

All you need to focus on is how far your impact was away from your POA and use your reticle as a measuring stick then dial accordingly.

Why worry about measuring......dial to your impact........

 

[4xforfun]

Why worry about measuring......dial to your impact........

+1

 

[Epraslick]

It is not metric. It stands for miliradian. Not military nor metric.
One mil is 1/1000th of what you are using. One YARD at 1000 YARDS, or one METER at 1000 meters and so on.
i.e. At 100 METERS it is 10 centimeters or at 100 YARDS it is 3.6 inches.
Mil scopes are graduated in 1/10th of a mil. So one 'click' is worth .36 inches at one hundred yards.
I hope the above helps.
I was never sure why this seemed to become the norm in the USA with scopes.

This is the best and most accurate reply. A mil is a 1/1000 of anything. If using yards (inches), 100 yards=3600 inches. One mil (1/1000)=3.6 inches. A 1/10 mil scope will move it .36".

 

[icu812]

Why worry about measuring......dial to your impact........

Off a bench, absolutely. From an akward shooting position in the field, not so easy. Removing your support hand to dial a turret while maintaining a steady sight picture isnt possible in all situations . Its just another tool in the tool box, thats all.

 

[Jammer Six]

There is no "advantage" to either system.

 

[sscoyote]

The true beauty of mil or MOA systems is that most ballistic programs calculate bullet drop/drift in both subtensions. If using subtension for reticle rangefinding (rarley accomplished these days), the mil-ranging formula in it's simplest form can be used with any angular measurement from mil to MOA to archery sight pins if one wishes. As it turns out the mil-ranging formula also defines downrange zeroing with any subtension/turret click as well. All this stuff takes time (and motivation) to learn though.