How to use Mil-Dots?

M

Mosin-Marauder

New member
My Scope on my .22-250 has 10 Vertical and 10 Horizontal Mils counting the center cross hair and the 4 thick edges. How do I use these for a holdover? Would keeping my power set at 10x be a good idea for 0-500 meter shooting? Could I still use the mils as a hold over tool if j changed the magnification? Is there any way I can write down the distances the mils represent like a BDC or something?
 
I though Mildot Master would only help with ranging, it is a simple slide rule.

If you want to use mildots for hold over, you need to do 2 things, first consult you scope documentation to see (assuming it is a variable power, second focal plane scope) what power the mil dots are intended to be used.

Second, chronograph your load and run the numbers through a good ballistics calculator (such as JBM mentioned above)and see at what ranges your load will hit 1 mil, 2 mils, 3 mils, etc.

For example, my 6.5-06 LR rig, with a 200 yard zero, the first mil mark would be at ~350 yards, the second dot would be ~475, the third would be ~600, and fourth would be ~700.

You will need to figure out where your rifle shoots with you load and run the numbers.

The down side to this, particularly at longer ranges, is the dots can get fairly big compared to the target. I did this for a while, and finally settled on printing out the elevation drops for my load and taping it to the side of my scope.
 
To use them effectively you need a good drop chart for the bullet and velocity you are shooting. There are several on the web, I have been using Hornady`s lately, you can find it on their web page. When you move from the power the mil dots are calibrated at, which all I have seen is the highest power on the scope, they are no longer mil dots. If you drop to 1/2 power your mil dots are now 2 mils apart. At 1/3 max power the mil dots are 3 mils apart.
 
Mils are nothing but a different angler measurement (not metric)

1 MOA is 1.047 inches per hundred yards

1 Mil is 3.43 inches per hundred yards.

Lets say your rifle is sighted in for 100 yards, and your target is 500 yards away.

Lets say your ballistic program says your bullet drops 10 inches at 500 yards

10 / MOA or 1.047 is 9.55 or you hold over 9.55 MOA

10/Mil or 3.43 is 2.9 mils so you hold over 2.9 mils

Everyone should have a drop chart for their rifle /ammo. If using mils make the drop chart in hold overs in mils, if using MOA make the drop chart in MOA.

That way when you range your target you can look at your chart and see how many mils or moa's to adjust for.

Its not really difficult. Personally I like to adjust. So I come up 9.55 min or 2.9 mils depending on what scope I'm using.

Both Mils and MOA can be used for range finding. But that isn't the question, its just as easy.
 
How do I use these for a holdover?
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Kraigwy's explination is best. I also like to use an app I downloaded on my phone, Strelok. I started with the free version and liked it enough I purchased the pro version.


Would keeping my power set at 10x be a good idea for 0-500 meter shooting?
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With a SFP scope the reticle needs to be a specific size. Your instructions that came with the scope should tell you what power that is.


Could I still use the mils as a hold over tool if j changed the magnification?
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Yes. I have a Swarovski 5-25x50 and I have two drop charts for it, one for when it's at max power (25x) and one for 15x. On 15x I can use the reticle at 1200 yards.

Is there any way I can write down the distances the mils represent like a BDC or something?
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Absolutely, you just need to know what your load is doing. I like zeroing at 100 yards then shooting 5-10 rounds at 300. I measure the drop and then know what my load is doing at that elevation/temp. I plug those numbers into Strelok and it adjusts for different elevations/temps.
 
10x is too high for close range. Scope will be out of focus.
A mil is a military unit of angular measurement equal to the angle subtended by 1/6400 of a circumference.
1" = 1,000 mils. The dot on a scope doesn't necessarily have anything to do with mils. The term 'Mildot' is a marketing term used to describe a reticle.
The vertical dots can be used as aiming points by holding each on centre, firing and seeing where the bullet hits. The horizontal's can be used for lead. Either way, like AllenJ says, you need to know your load and your rifle.
 
It was mentioned before and I'll expand on it. If your scope is second focal plane (reticle size doesn't change with magnification change) then the mils in the reticle are only true at 1 magnification setting (usually max magnification or close to it). So for every other magnification setting, your mils are a fraction of their true measurement.

What is the magnification range of your scope(2.5-10)?
What magnification are the mils true?

With these 2 I can run it through the conversion calculator I created and post up the mil measurements for each magnification setting.
 
I always understood the mil (milliradian) dots along the reticle to be intended more for rangefinding than for holdover/lead. Of course they could be used as a BDC to some degree; how much would very much depend on the load and it won't be a standard distance. As mentioned they will only work predictably at a given power factor, which should be supplied by the scope manufacturer.
 
Not really Ifish:

Mil marks, as well as MOA marks are constant. A mil is a mil, a moa is a moa regardless of range.

You use either with a ballistic program or data sheet drop chart. Knowing the "inches" your round drops at a given range, you hold over, the mil or moa marks tells you how much to hold over.

For example you're shooting 600 yards and your drop chart says your bullet drops 7 inches.

A MOA at 600 yards is 6.258 inches.

6.258 would be 1.82 mils,

So if using a MOA scope, you would hold over 6.258 MOA, and if using a MIL based scope, you'd hold over 1.82 mils.

Both would be holding over 7 inches.

The only place where velocity, Bullet BC etc comes in is determining the drop at a given range. Once that's known you can use either to hold over.
 
Actually Kraig, Ifish is right.

Mildot reticles are intended for ranging (as you know I am sure), and while a mil is always a mil, but if your scope is second focal plane, then the lines on the reticle will only be mils at a specific magnification. Fixed power, or first focal plane scopes do not have this problem.

And they can be used as a BDC, by using the dots as aim points for long range rather than spinning the knobs.

What he means by "won't be a standard distance" is that unlike a standard BDC reticle that would have lines for 200, 300 and 400 yards (or whatever) the mil dots probably won't line up perfectly with nice round ranges. I am pretty lucky in that (like I mentioned above) my 6.5-06 at my normal altitude with a 200 yard zero, the mil marks below the crosshair are the correct elevation hold for 350, 475, 600, and 700 yards. Running the numbers for a .308 178 AMAX @ 2600 FPS (using the same sight height and altitude) would be 320, 425, 525, 610. This is what he means by "won't be a standard distance."

It does work, the biggest drawback is that the mildots are not very precise if you are shooting something that isn't very big. The crosshair works much better. The other disadvantage is that at any range where wind is a factor, if you hold off for wind, often your aim points in the scope are not actually on the target at all. You are holding 3 mils high and 1 mil windage, the target is actually kind of out in space away from the crosshair.

This is the main reason I stopped using the MilDot as a BDC, and went back to a drop chart taped to the scope, and spinning the elevation knob. I still hold off for wind, but it is much easier doing that when the target is on the horizontal line of the reticle, than "that looks about right"
 
Question about dialing in. When finished do you return to some pre-established point, say dialed in at 100 yards?
 
Question about dialing in. When finished do you return to some pre-established point, say dialed in at 100 yards?
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Yes, after zeroing your rifle set your turret knobs to zero, then you can easily return to your zero setting after dialing up a shot.
 
Emcom:

A mil is a mil, a moa is a moa. I stayed away from FFP/SFP. Regardless of scope the recital has to reflect mil/moa to be a mil/moa scope. When one buys a scope, the directions tell you what power the scope needs to be set to, to for the reference dots to reflect mil/moa's. (not all are on the max power).

Mils are use to measure distance, but I wouldn't go so far to say that is their primary purpose.

I've used and taught Mils before they started showing up on rife scopes. Mainly in Machine Guns. The T&E on most MGs are in mils, and you adjust in mils. For example using a range card, you mark possible target points. You lay the gun at one point, and mark that as zero, then each target point is so many mils right, left, up, or down from your zero. In doing that, you can engage targets you cant see such as at night.

Horizontal distance can also be measured in mils using the index finger. For example, the average index finger is 50 mils. So in plotting targets for the range card, for example, you can use the extended finger to see that from the ref. point, target X is 1 and 1/3 finger width, or 75 mils right.

Or, if the spotter says "shift right 100 mils, you can simply hold your finger out to the right side of the sight, holding the hand still move the sight to the right of the finger, (move is 50 mis) do this a second time, and you shifted the gun 100 mils.

1 mil is 1 yard at 1000 yards so 50 mils is 50 yards at 1000 yards

Granted shift 50 yards isn't normally called for when hunting, but the principle is the same.

Knowing 1 mil is 1 yard at 1000, we can assume that 1 mil is 18 inches at 500 yards. So if we are shooting a target at 500 yards and the wind is a fv value 15 MPH wind, we check our data card and release we need a horizontal hold of 1.4 mils. to correct for this wind, we simply use the horizontal scale on the recital to hold off.

Regardless, the scope power has to be set to reflect true mils (or moa on moa scopes)

-------------------------------------------------------------------------------

KCUB:

Question about dialing in. When finished do you return to some pre-established point, say dialed in at 100 yards?
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For me, depends.

When hunting, no. When I sight in the scope I zero the elevation and windage knobs. The scope dial is marked 1, 2, 3, etc. So on MOA scope the 1 would be 1 MOA, from 0, with normally 1/4 clicks in between. The Mil scope also is measured in 1, 2, 3, etc. but it is mils. The Mil scope normally has .1 mil clicks.

So if your scope is set on one number, and your target range calls for a another number, you move to that number. Let say you need to come up from zero 5.25 MOA. Regardless of where your scope is set. You move it to 5 and add one more click to get the .25. Same with mils.

HOWEVER. In rifle shooting, I shot iron sights. On the M1 or M14 you can get your zero and set the elevation dial to that zero. So when the 2 on the dial is lines up with the mark on the sight base, you are sighted in for 200 yards and can set your sights to any mark without counting. But the ammo has be match the sights.

I use the score or data book. I know how many clicks up for each range for the ammo I'm using because its written down. After firing on each yard line, I put my sight back into the bottom, then when I get to the next yard line I count up the clicks needed for that distance. Its a habit I developed a long time ago because when I first started shooting, I forgot, and ended up adding my elevation twice.

To see the witness marks on my M1/M14 sights, I have to put on my reading glasses. That's a bit more flopping around then want when in position so I just count clicks.
 
Excellent explanation Kraig and I do understand it's just a fixed measure like MOA, which is what I learned to use. But with regards to using the mil dots like a BDC - when looking at the reticle, isn't the milliradian the actual size of the dot itself and not the distance between the dots on the reticle? For instance if you could fit two dots between the actual dots you see on the reticle, the space between the dots would be a 3 mil difference center to center? Meaning holding over by an actual dot on the reticle would represent a little over 10 inches @ 100 yards (in terms of POI)? I do wish to be sure that I understand correctly.

I didn't mean to infer that a mil-dot reticle couldn't be used as a basis for hold-off/hold-over - it can of course. Only that I understand that it was meant more for purposes of ranging distant targets primarily and it won't be in very round easy-to-remember numbers as a BDC for most shooters who primarily shoot less than 500 yards.
 
I'm not speaking for Kraigwy but my mil-dot scopes has diamonds instead of round dots to mark the mils, in between the diamonds is a hash mark for half mils.

From center of diamond to the next center of diamond is 1 mil (3.6 inches) center of diamond to the next corresponding hash mark is .5 mils or (1.8 inches).

I have cheater sheets taped to my rifle stocks with bullet drops, MOA and MIL information so it's not hard for me to use my MIL recticle as a BDC for quick shots if I desire to.

That being said I prefer to dial-up when possible and on my MOA scopes I have to dial-up or use the hold over estimation system, which at 350 yards or less is not that hard to do.
 
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Don't get hung up on mil "DOTS". Think back to your High school geometry. A line drawn on a piece of paper only represents a line, I line is a dividing point and has no width.

The same with mils and moa, its a point that cant be measured only represented.

I have a verity of scopes, some show the dot as circles, some have football shaped mil representatives, and some have lines or tick marks. The center of each is the unmeasurable cross over point to the next mil. The center of the circle is one mil from the center of the next circle, or tic mark

The same for moa marks on a radical. Some moa scopes come with little circles, some with tic marks. You measure from the center of the circle/tic mark to the next. On moa scopes 2 moa between marks are common.

I think a brief description of what a mil is, is warranted.

Draw a circle. From the center of the circle to the line representing the outer edge, or circumference is the radius.

Measure the radius. Then from the point where the radius intersects the circumference, take the length of the radius to another point on the circumference. Then draw a line from that point to the center of the circle.

You have a triangle. This triangle is called a Radian. Divide the out side (circumference side) by 1000 and you have a "mil-radian". This is what we call a Mil, a mil is actually called a mil-radian.

Go toward the center of the circle, you'll see the mil-radian is quite small, but its still a mil-radian. The larger the circle, or longer the radius the more distance between one mil-radian to the next.

The lines you draw can be as thick as you want, but the actual line is the center of the line you drew and is immeasurable. Line your lines in your HS geometry classes.

So in using mils (or moa's) ignore the shape. Use the center. It takes a great deal of practice to divide the points between the center of one, to a point between it and the center of the next, to determine if its 1/2 mil, 1/3 mil, 1/5 mil, etc etc.
T
he point between one mil to the next is 3.43 moa.

In small arms, (until recently) the MOA was used. A MOA very nearly 1 inch per hundred yards.

In military fire control work the mil is used. The mil is an angle whose tangent is 1/1000. or 1 unit at distance of 1000 units.

There are actually 6183 mils in a complete circle. This number is not divisible into fractions as a whole number.

The Artillery Corp adopted the Artillery Mil which is 6400 parts. The infantry used the 1/6280. The infantry mil was dropped in favor of the Artillery mill.

The Artillery mil is 3.375 minutes. This is easy to use when direction artillery or machine gun fire but confuses many as the actual mil is 3.43.

If you're taking out a target with a shell with a large bursting radius, or laying searching fire with a machine gun, it doesn't matter.

If you're trying to get all your bullets into one hole at 1000 yards, the difference between 3.375 and 3.43 does matter.

Thus using the outer edge of the circle representing a mil in your scope, and the center of that circle, likewise matters.

Not to confuse, but maybe help, to determine how many radians in a circle, multi PI times two. 2 * 3.1416 is 6.2832. there are 1000 mil-radians in a radian so that number becomes 6283.2. Or there are 6283.2 mils in a circle.

That's a bit different then the 6400 used by the military.

I think a lot of the confusion comes from he term "mil dots" , disregard the "dot" as the actual dot has no measurement.
 
kraigwy said:
For example you're shooting 600 yards and your drop chart says your bullet drops 7 inches.

A MOA at 600 yards is 6.258 inches.

6.258 would be 1.82 mils,

So if using a MOA scope, you would hold over 6.258 MOA, and if using a MIL based scope, you'd hold over 1.82 mils.
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I think the hold over in your example on a MOA scope should be 1 MOA, or 0.3 MIL on a mil scope.

-TL

Edit to add:
It is quite easy to figure out the hold over. Ask for bcd in MIL on the ballistics software and use it. If you already have bcd in MOA, multiply by 0.3 to have MIL.
 
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