I still don't understand inches drop versus MIL drop
- Thread starter tpcollins
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johnwilliamson062
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Now I'm only a few university level mathematics courses away from the answer!
math teacher
New member
A milliradian (mil) is 3.438 minutes of arc so it subtends roughly 3 1/2 inches at 100 yards, or one yard at a thousand.
For anyone who hasn't figured it out.
Mil drop is the angular measurement so you can adjust your scope to put the bullet on target. Mils and MOA are just different ways of measuring angle, so sometimes you'll see an MOA drop table as well.
Inch drop is the actual vertical distance drop from the zero range to the further range. You can convert inches into MOA or Mils to figure out your scope corrections to put the bullet on target. Sometimes you'll see this in meters or centimeters as well, which is just another measurement of distance.
Hope this is helpful.
Jimro
Mil drop is the angular measurement so you can adjust your scope to put the bullet on target. Mils and MOA are just different ways of measuring angle, so sometimes you'll see an MOA drop table as well.
Inch drop is the actual vertical distance drop from the zero range to the further range. You can convert inches into MOA or Mils to figure out your scope corrections to put the bullet on target. Sometimes you'll see this in meters or centimeters as well, which is just another measurement of distance.
Hope this is helpful.
Jimro
MIL-Metric...Centimeters/Meters
MOA -English Standard Inches/Yards. It's a matter of which you prefer to use. Or if you already have a scope reticle which is calibrated for one or the other, knowing which one you have. MIL based systems make the math a little easier if you use the reticle to range unknown distance targets, except for you need to be able to wrap your mind around being able to estimate the size of something in meters or centimeters. Used vertically, and horizontally.
That fries my brain, so I like MOA based reticles. If you are using a range finder, then its just a matter of using the right trajectory chart. I think most military/tactical units these days are using the mil based system. Depending on how flat your cartridge is, unless you are shooting at things beyond 300 yards, a good scope with a duplex reticle is fine. Unless you just want to spend money on something that looks cool. There is a reason they are expensive. If you use one, it is helpful to learn to think of your trajectory and windage in MOA or MILs instead of inches, or centimeters. (I tend to think inches, so I like MOA based stuff)
How I practice this is to range objects at different distances with the scope (no shooting, just math) and then check with a range finder. I'm usually within a few yards. It does require practice though. It really is the reasoning behind having a scope that is capable of this. If you're not going to use it for that, then really no need to waste your money. If you have more than one, its best if they are both of the same type
If you are in the best of the west mode, then you need to (should) have a good scope with a calibrated reticle and turrets, and good optics/coatings. Not just something with lines on it that are supposed to correspond to something.
Herein is where the cash starts to come into the game. One other thing, you need a rifle capable of accuracy fine enough to put the bullet where your calculations and aim says it should go, and lots of practice. Kind of stating the obvious, but you might be surprised at how many folks think an expensive scope will make their rifle accurate when they shoot it once a year with whichever ammunition WalMart happens to have that day.
Sorry for the long response, but its relevant to the difference between the two. Otherwise, it doesn't matter. You will either miss high, low, left, or right.
MOA -English Standard Inches/Yards. It's a matter of which you prefer to use. Or if you already have a scope reticle which is calibrated for one or the other, knowing which one you have. MIL based systems make the math a little easier if you use the reticle to range unknown distance targets, except for you need to be able to wrap your mind around being able to estimate the size of something in meters or centimeters. Used vertically, and horizontally.
That fries my brain, so I like MOA based reticles. If you are using a range finder, then its just a matter of using the right trajectory chart. I think most military/tactical units these days are using the mil based system. Depending on how flat your cartridge is, unless you are shooting at things beyond 300 yards, a good scope with a duplex reticle is fine. Unless you just want to spend money on something that looks cool. There is a reason they are expensive. If you use one, it is helpful to learn to think of your trajectory and windage in MOA or MILs instead of inches, or centimeters. (I tend to think inches, so I like MOA based stuff)
How I practice this is to range objects at different distances with the scope (no shooting, just math) and then check with a range finder. I'm usually within a few yards. It does require practice though. It really is the reasoning behind having a scope that is capable of this. If you're not going to use it for that, then really no need to waste your money. If you have more than one, its best if they are both of the same type
If you are in the best of the west mode, then you need to (should) have a good scope with a calibrated reticle and turrets, and good optics/coatings. Not just something with lines on it that are supposed to correspond to something.
Herein is where the cash starts to come into the game. One other thing, you need a rifle capable of accuracy fine enough to put the bullet where your calculations and aim says it should go, and lots of practice. Kind of stating the obvious, but you might be surprised at how many folks think an expensive scope will make their rifle accurate when they shoot it once a year with whichever ammunition WalMart happens to have that day.
Sorry for the long response, but its relevant to the difference between the two. Otherwise, it doesn't matter. You will either miss high, low, left, or right.
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buckhorn_cortez
New member
100% WRONG. A radian is neither metric nor standard measurement.
It doesn't matter the measurement system as a radian is a trigonometric description.
A radian is an arc on the outer circumference of a circle that is equal in length to the radius. The angle subtended from the center of the circle to the outer ends of the radian arc is the radian angle - 57.3 degrees per radian.
There are 2Pi radians in a circle or - 6.2832 radians.
Why 2Pi radians? Because the circumference of a circle is: C = 2 x Pi x R (radius).
Isn't that interesting...? The circumference is 2Pi radiuses and there are 2Pi radians in a circle - Holy moly - it's the same thing - just a different way to describe it!
Just like a radius is neither metric nor standard - neither is a radian. Either distance (radius or radian arc) measurement can be in inches, centimeters, furlongs, nautical miles, chains, rods or any other type of length measurement.
A milli-radian is simply 1/1000 of a radian as "mil" is one thousandth. So, there are 6,283 milli-radians in a circle, each one having a milli-radian angle of 0.0573 degrees (1/1000 of 57.3).
100% WRONG AGAIN. Minute-of-angle (MOA) is simply a different description of an angle subtended at the center of the circle.
There are 60 minutes in 1 degree. There are 360 degrees in a circle. 60 x 360 = 21,600 minutes in a circle. Minutes are not metric or standard - they're just a description of an angular unit.
As with a MIL, you can see that there is not a unit of measurement associated with the MOA description. It is a geometric description instead of a trigonometric description.
1 MIL angle = 3.438 MOA
At 100 yards - 1 MIL = 3.6 inches.
At 100 yards - 1 MOA - 1.047 inches
At 100 yards - 1 MIL= 91.44 millimeters or 9.14 centimeters
At 100 yards - 1 MOA = 26.59 millimeters or 2.66 (rounded up) centimeters
Instead of yards, we could change the distance to meters and still have inches or millimeters / centimeters for the MIL or MOA measurement at the end of the 100 meters. It doesn't matter because MIL and MOA are simply describing an angle that can be extended to any distance in any measurement system.
As you can see - neither MIL nor MOA have any relationship to a specific unit or type of measurement - they are simply different descriptions of angular measurement.
I understand - it's math and that's even harder than English...
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what buckhorn said.
It is explained and you can practice here: http://www.shooterready.com/lrsdemo.html
It is explained and you can practice here: http://www.shooterready.com/lrsdemo.html
Gee thanks...I don't think I said that one or the other equals anything, and I don't remember trying to give a Geometry or Trigonometry lesson either. In general terms, MOA is an Imperial measurement representing minutes and degrees just as you said.And also just as you said one Mil is 1/1000th. 1 milliradian being 10cm at 100 meters. So without the geometry and trigonometry lesson:
Imperial: Minutes, degrees, miles, feet, inches, pounds, ounces, gallons etc.
Metric: milliaradians (sounds like millimeters don't it) Meters, centimeters, kilometers, liters, and so forth.
Here: https://www.precisionshooting.com.a...4/02/moavsmilliradian-angularmeasurements.pdf
Notice the photo of the S&B PMll scope, 1 click = 1cm. Is that metric? If it's not, you better call them and let them know, cause they charge a lot of money for those things, and they need to change it if they are 100% wrong.
Is 1/8 or 1/4 an Imperial fractional measurement, as in 1/4 MOA? If not, then please call NightForce for me and help me get my money back. I cant imagine how I've been able to shoot so many things a half mile away if that's wrong, and I want a refund.
I believe I was relating to the practical application of ranging objects, and using the equipment to fire projectiles at a target with a rifle, not giving a math lesson, and I wasn't talking about clicking the mouse button at a target on a computer screen. I probably have a fired 308 case in the shop for every one of those mouse clicks.
I will be polite, and say that one may have missed the simple example that I was using to explain something that may be somewhat complicated to most folks. What may fry a lot of peoples brains, is how many centimeters is a deer from brisket to back? Well, about 18 inches, wait...let me see 18x2.54 ahhh 45.72 cm.
-is not= I guess English really is as hard as math.
I think most folks understand that was the point. Lets go shooting and be friends. I said I will be polite, so I will leave it at that.
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gman3 said:
You still don't get it. Milliradians are not metric, they are unitless. It does not matter what you use with them. If Noah's ark (30 cubits high) is 5 mils in your scope, then it's distance is 1000*30/5 or 6000 cubits away from you. It works the same in every unit system.
buckhorn_cortez
New member
You don't get it.
Adjustments on a scope, whether MOA or MIL are UNITLESS. Honest. Europeans can use MOA scopes and they do their corrections in the metric system.
The fact YOU like to work in inches, feet, yards is fine - you can do that with MOA or MIL adjustments - it doesn't matter.
Clicks on a MIL scope are usually 1/10 MIL adjustments. That has NOTHING to do with metric adjustments.
The change can be in millimeters, inches, yards, meters, furlongs, fathoms, leagues, etc. Whatever unit counting system you want to use.
As stated by another poster - radians and milli-radians are unitless. They are only numbers and can be associated with either metric or inch measurements - or any other unit counting system you want to work with.
Really - the milli-radians don't care. Think of them as being totally agnostic - they can be whatever you want them to be.
I have a front focal plane MIL scope. I do all of my calculations in yards, feet, and inches. It works just fine.
One click is 0.1 milli-radians - or about 3/8-inch change at 100 yards.
Thank you. And the cubits are a nice touch, I totally forgot that unit of measure.
Adjustments on a scope, whether MOA or MIL are UNITLESS. Honest. Europeans can use MOA scopes and they do their corrections in the metric system.
The fact YOU like to work in inches, feet, yards is fine - you can do that with MOA or MIL adjustments - it doesn't matter.
Clicks on a MIL scope are usually 1/10 MIL adjustments. That has NOTHING to do with metric adjustments.
The change can be in millimeters, inches, yards, meters, furlongs, fathoms, leagues, etc. Whatever unit counting system you want to use.
As stated by another poster - radians and milli-radians are unitless. They are only numbers and can be associated with either metric or inch measurements - or any other unit counting system you want to work with.
Really - the milli-radians don't care. Think of them as being totally agnostic - they can be whatever you want them to be.
I have a front focal plane MIL scope. I do all of my calculations in yards, feet, and inches. It works just fine.
One click is 0.1 milli-radians - or about 3/8-inch change at 100 yards.
Thank you. And the cubits are a nice touch, I totally forgot that unit of measure.
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buckhorn_cortez
New member
1/4 MOA can be whatever you want it to be. It is not Imperial just because it's "fractional." 1/4 is a ratio that's all.
1/4 = 0.25 and that's a decimal representation of the fractional ratio.
Neither 1/4 nor 0.25 are Imperial or metric - they're just NUMBERS.
Want to see?
1/4 MOA = 6.64 millimeters change at 100 yards. That's the change in metric.
Or, it can be 1/4 MOA = 0.26 inches at 100 yards. That's the change in Imperial measurement.
Both are exactly the same - they're just in different units of measurement.
The MOA doesn't care. Like a MIL, MOA has no allegiance to a specific measurement system.
buckhorn_cortez
New member
And there, in a nutshell, is the crux of the biscuit. YOU personally don't like working in the metric system because you're used to inches, feet, yards, etc.
If you grew up nearly anywhere else in the world, you'd have exactly the opposite problem. You'd find trying to convert from metric measurements to Imperial equally as difficult.
The nice thing? You can use EITHER UNIT SYSTEM with an MOA reticle or a MIL reticle.
You just do the calculations in the system you're used to using because (one more time) - the MOA and MIL division are UNITLESS until you apply the unit measurement system you want to use.
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buckhorn_cortez
New member
Bingo! Thanks for a really nice illustration of using MIL reticle divisions in a hunting situation with inches, feet, yards, etc.
chris in va
New member
All I know is if my reticle is dead on at 100 yards, I have a holdover of -1.5 mil dots at 300 with my .223 bolt. Works for me.
People sure seem to make "simple" "complicated".
Once you understand what a radian is, and that a mil-radian is nothing more then 1/1000th of a radian, it all comes together.
Draw a circle. The point to the center of the circle is the radius. Take the length of the radius (lets say its 3 inches) laid along the circle circumference, then back to the center of the circle. That gives you a triangle. That is a radian. 1/1000 of that is a mil-radian, commonly called a mill. Close to the center of the circle the mil is smaller the toward the outside of the circle. You can measure that distance in inches, yards, meters, milometers, rods, cubics or what ever. Using our 3 inch radius, at the outside of the circle, the mil will be 1/000 of 3 inches. It will be 1/1ooo of 1.5 inches at have the length of the radius, and that's how you can figure distance IF you know the size of the target.
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Now to have fun have someone figure out mils, radians, minutes, etc. using common core math.
I had a grade school teacher in one of my shooting classes telling me how great Common Core was.
I had her stuttering trying to compute mils, cosines for angle fire and a few other shooting math problems.
Once you understand what a radian is, and that a mil-radian is nothing more then 1/1000th of a radian, it all comes together.
Draw a circle. The point to the center of the circle is the radius. Take the length of the radius (lets say its 3 inches) laid along the circle circumference, then back to the center of the circle. That gives you a triangle. That is a radian. 1/1000 of that is a mil-radian, commonly called a mill. Close to the center of the circle the mil is smaller the toward the outside of the circle. You can measure that distance in inches, yards, meters, milometers, rods, cubics or what ever. Using our 3 inch radius, at the outside of the circle, the mil will be 1/000 of 3 inches. It will be 1/1ooo of 1.5 inches at have the length of the radius, and that's how you can figure distance IF you know the size of the target.
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Now to have fun have someone figure out mils, radians, minutes, etc. using common core math.
I had a grade school teacher in one of my shooting classes telling me how great Common Core was.
I had her stuttering trying to compute mils, cosines for angle fire and a few other shooting math problems.
No it's 100% correct the radian is the SI accepted mesurement of angles.
While MOA isn't "inches and yards" it is not the SI accepted unit.
Yes they are they are MOA and MIL are in fact units.
It's just easy to use MIL with the metric system
1 MIL = 1 meter at 1 kilometer
And likewise MOA is much easier in inches since 1 MOA is very close to 1 inch per 100.
buckhorn_cortez
New member
Technically - no. The shape being made is not a triangle as a triangle has three straight sides. The shape being formed for a radian or milliradian is pie shaped (one side is curved) because it is made by the edge of a circle.
That shape is called a "sector." It is made up of two radii (straight sides formed by radius length lines) with a curved third side made by the circumference of a circle.
The radian or milliradian is always the same angle no matter the distance from the center. The distance between the two radii forming the included angle (sides of the sector) increases as the distance from the center point increases because the radii (sides of the sector) are diverging.