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December 9th, 2008, 12:52 AM #1
Mildots, EVERYTHING you want to know.
Ok, so I decided to do a post regarding mildot reticle rifle scopes to help some people out with learning how to range and use hold over with them. Please keep in mind that you can find a great deal of this information at http://www.mildot.com . A good place to apply some of what you learn at the end of this is a simulation (not a game) called shooter ready. You can find it here http://www.shooterready.com/lrsdemolow.html .
I’m not going to get into great detail about the measurement of the system or why it works, if you’re interested in that, you can find it on that website or other places by searching of “mil dot angular measurement.” Basically, what you need to know is that mil’s are not a fixed measurement, they are an angular measurement that changes with distance and what scale you’re using. This sounds confusing, but basically a mil equals 1 yard at 1,000 yards, 1 mile at 1,000 miles, 1 meter at 1,000 meters, 1” @ 1,000”, some of you get the idea. It is NOT necessarily metric, but just because it is based on a 1,000 system, it does translate fairly easily to that. Either way, it’s an angular measurement; mil stands for milliradian (radians being angular).
Reticles
Ok, now to get down a bit more to application…..
FIRST you need to know what type of mil dot scope that you have, there are quite a few variations of mil dot scopes, reticles, tactical milling reticles, etc. Most scopes that people buy are Second Focal Plane reticles, this means that your reticle will only accurately judge distance and/or hold overs at one predetermined power (this could be 10x or any other magnification setting as determined by the manufacturer). The way that you can determine if your scope is a First Focal Plane, or Second Focal Plane reticle is to watch the reticle as you zoom in and out. If the reticle appears to get larger (not just the object you’re viewing, but the reticle), then you have a First Focal Plane reticle; IF the reticle stays the same size, but the target gets larger then you have a Second Focal Plane scope. The difference is that with a FFP (first focal plane) reticle, you can range at ALL magnifications, with the Second Focal Plane Reticle, you can range only one predetermined power that is determined by the manufacturer. Sometimes this is the highest power, but on some higher powered scopes, manufacturers sometimes use a lower power so that you don’t have to try to mil at 16x; so they may use 10x or 12x, etc. You have to do the research on your scope to find out, or physically go measure (the best way) to know. For fixed power scopes, you do not have to worry because it only has one magnification to mil with and this should be accurate. If you are interested in finding out EXACTLY where your scope ranges properly, there’s a wonderful paper by Lindy from sniper’s hide here:
http://www.arcanamavens.com/LBSFiles...ScopeChecking/ .
Ok, next I’m going to now talk about some differences in mildot reticles. (I actually use a Generation II mil dot reticle, which has mil dots, and then it has hashes in between the mils which represent ½ mil.) We will be looking at the standard mil dot reticles; which there are basically 2 types. The standard mil dot reticle (or Army reticle) as some people like to call it, has ROUND mil dots and looks like this.
The U.S. Marines use a mil dot reticle that is slightly different and has “oval” or “football” mil dots and will look like this.
Neither of these reticles is superior to the other, they are just different. When you are ranging with mil dots, there are some fairly simple formulas that you will have to remember, along with what the marks in your reticle signify in terms of measurement.
In order to range a target with your reticle, you need to know a few things. You MUST know the height of your target. There are several formulas that I will be posting, so this can be the height of the target in meters, yards, or inches; it will all depend on which formula you would like to use. Either way, you must know a height that is pretty close to the actual height, so that you can use the angular measurement of the reticle to determine the distance to the target. The other thing that you need to know is the measurements of your reticle. With the “Army” reticle (round dots) these will be your measurements:
From the center of one dot, to the center of the other is 1 mil. From the inside edge of one dot to the inside edge of the other dot is .8 mil’s. From the horizontal crosshair to the inside edge of the first dot is .9 mils. Obviously the optical center between the 2 dots is going to be .5 mils. The mil dot itself is roughly .2 mils (actually .22), so from the center of one dot to the edge of the next is also .9 mils. When you get better at using the mil dot reticle and judging distances, you will actually start to look at finer measurements like this:
Now with the Marine mil dot reticle (or ovals), the measurements will be slightly different, and your measurements will be like this:
From the center of the oval to the center of the next oval is still 1 mil. From the inside of one dot to the inside of the next dot is .75 mils. The optical center between these 2 dots is also .5 mils. From the crosshair line to the edge of the first mil is 7/8’s mils, or from the center of one mil dot to the inside edge of the next mil dot will also be 7/8’s mil. The mil dot itself is actually .25 mils.
Ranging
Okay, so now you know the measurements of your reticle, what power it’s actually at, and the height of your target (either from measuring some specimens, or just looking it up). Now you need to go prone or get on a bench, and hold VERY stable. It doesn’t really matter exactly how you hold the reticle, as long as you know your measurements along it. You can start with crosshair post, or the center of one of the dots. If you can’t make it be dead on mils, or dead on in the center, you might try adjusting your point, so that you can use the ¾ mil spots, or some others. This is when you are only in the beginning phases, to kind of help you get a feel for it. As you get better, you’ll be able to use your eyes to judge the center, and then just the center of that center. Depending on your distance and magnification for your scope, you should come up with a number, maybe something like .75 mil’s, or maybe it’s 1.75 mils (it doesn’t matter) as long as you have a number that you feel pretty confident in and have double or triple checked. So what do you do now with this measurement?
This is where the formulas are necessary and come in handy. There are LOTS of formulas, and which one you use really doesn’t matter, as long as it’s something that you can remember, or come up with a number that’s useful to you. I will list LOTS of formulas, so that you can choose the one that best fits you.
Distance to Target(Yards) = [Height of Target (Yards) * 1000] / Image Size(mils)
Distance to Target(Yards) = [Height of Target (Inches) * 27.778] / Image Size(mils)
Distance to Target(Meters) = [Height of Target (Inches) * 25.4] / Image Size(mils)
Distance to Target(Meters) = [Height of Target (Meters) * 1000] / Image Size(mils)
Distance to Target(Meters) = [Height of Target (cm) * 10] / Image Size(mils)
Now you simply need to plug in your information to get your distance.
Say I am shooting at a silhouette shaped target that is 36” tall and appears to be 1.5 mils in my reticle, and I want the distance in yards. I am going to use the formula for inches because I know the target’s height in inches. I would put in my calculator (36 x 27.77)/1.5 , to get an answer that the target is approximately 666.48 yards away. If I was doing this calculation with a height of target in yards and want the distance in yards, I’d plug in (1yard x 1,000)/1.5, to get an answer of 666.67 yards to target. The formulas will all work, it will just depend on what you know the target’s height in, and what kind of answer you would like to get (yards or meters). So now you know the distance to your target.Last edited by Tomcat088; January 15th, 2013 at 02:25 PM. Reason: fix broken picture link

December 9th, 2008, 12:54 AM #2
Re: Mildots, EVERYTHING you want to know.
Doping
In order to “dial in” your scope and after knowing the range, you MUST know the ballistics of your rifle and load. This is usually accomplished by choosing a 0, and making all other measurements relative to that zero. Since most people don’t have access to a range longer than 100 yards, and it’s hard to get a zero that has 0 wind value at distance past 100 yards, most people use a 100 yard zero. You can use a ballistics program to give you an idea of how many inches of drop your rifle will have at what distance, or you can shoot at those distances and measure. If you are using a ballistics program, the more variables you can properly fill into the program, the more accurate the numbers will be. Helpful numbers for ballistic programs are the muzzle velocity of your bullet (chronographed, not advertised), weight of the bullet, ballistic coefficient of the bullet, temperature, barometric pressure, humidity, elevation, height of scope above bore etc.
Now, if you’re just trying to get hold overs for medium distances, most of those variables won’t make a huge impact. The most important of those would be muzzle velocity, bullet weight, BC, elevation of your area (how many feet about sea level), and the temperature. The most accurate way to get data is to go out in the field under good conditions, with a good shooter, and see how many inches of drop you get at what distance. This is usually kept track of in terms of number of inches of drop, say at 300 yards, and the bullet hits 3” lower than your 100 yard zero. This would usually be documented at 3.0” of drop at 300 yards. So now you have a number that says your bullet will hit 3.0” low at 300 hundred yards. So now what do I do?
MOA vs. Mil
We will now talk about a DIFFERENT measurement from mils, called Minute Of Angle. Minute of Angle is a different angular measurement from mils. Mils are based on milliradians, but MOA is based on degrees; but the systems are similar, they just translate to different values.
In America, since we like to think in inches, the MOA was convenient because ¼ minute of angle at 100 yards, equals ¼” at 100 yards. In other countries, most of their scopes are using milliradian reticles, and they adjust in mils, like .1 mil, .2 mil, etc. Most Americans like to think in inches; it kind of makes using a mil based reticle a bit more of a hassle because you had to do another conversion. There are scopes that are milling reticles that adjust in milliradians. If you can afford one of these or find one in your budget; most serious tactical shooters prefer them hands down over one that adjusts MOA. Either way, your scope is probably going to adjust MOA, so you have to learn some extra steps.
I want to start off by saying that MOA does NOT equal inches; MOA is also an angular measurement like the name implies. So, 1 MOA at 100 yards equals 1”; BUT 1 MOA at 300 yards, equals 3”. Do you see that the size of 1 minute of angle is not a set measurement; it changes with distance exactly the way the milliradian changes with distance? Let’s say that we had the situation from before…..at 300 yards your bullet will drop exactly 3.0” from your 100 yard zero. Your scope turrent will probably read “1 click = ¼ moa.” Since we are doing this relative to our 100 yard zero, that means that we want to make the bullet move 3”, well at 100 yards since 1 click equals ¼” this means that we only have to make 12 clicks, and we’re hitting dead on. From your 100 yards zero, you would say that your bullet required 3 minutes of elevation.
Let’s play devil’s advocate though and look at this backwards. What would happen if you had a 300 yards zero, but were shooting at a target that was at 100 yards? So your rifle is zeroed at 300 yards, if you shoot at a target that is at 100 yards, your bullet would hit 3” high. Now looking at that, how many MOA high, did your bullet hit? If you said 3 minutes, you’re WRONG. From a 300 yards zero, your bullet hit 3” high, which means that the bullet actually hit 1 minute high. I bring this up so that you will realize that 1 MOA does NOT equal 1”, it is all relative; at 300 yards, 1 MOA = 3”. This seems quite complicated right now, but you have to trust me on this, TRULY understanding minutes of angle will be your friend later when you start using hold overs and hold unders on a mil dot reticle.
Ok, I’m not sure if you have figured it out yet, but I did hint at this earlier…. If you are using a mil dot reticle scope, that has MOA adjustments, you’ve actually combined 2 different systems into 1 scope. It doesn’t make a lot of sense, but because Americans like to think in inches, many would not consider using milliradians, even though they aren’t metric; because of the appearance of the metric system. As a result, we ended up with the mess of 1 MOA on your dials, NOT equaling 1 mil dot in your scope. IF you ever want to use hold over and hold under with a mil dot reticle, you MUST remember that 1 mil = 3.438 MOA. I will say that again, they are not the same thing, 1 MIL = 3.438 MOA. This is where there will actually be a little bit of confusion. A true MOA, does NOT equal 1” at 100 yards, 1 MOA actually equals 1.0475” at 100 yards. Now when shooting at 100 yards, this isn’t really that big of a deal, but when you do the math, it means that 1 mil actually covers 3.6” (3.438 x 1.0475” = 3.6”). You will see some confusion in this area because some manufacturers of scopes don’t adjust their scopes to TRUE MOA; they actually adjust at 1” at 100 yards, as opposed to 1.0475” at 100 yards. Either way, if you’re not rounding, 1 MIL = 3.6” at 100 yards, or 1 MIL = 36” at 1,000 yards. If it makes it easier for you to remember, just think that 1 mil = 3.6 moa, although it’s actually just a short cut.
Hold Over and Hold Under
Ok, now on to for the shortcuts that you can achieve with a mil dot reticle. Now that you have an idea that 1 mil dot is equal to about 3.6 moa, say that you range a target and then look at your data. If your rifle is zeroed at 100 yards, and you see that the bullet will hit 3.6 moa low for the range to the target. Well that’s one easy shot, you just hold one mil dot OVER, and the bullet will hit dead center in that mil dot. What if the target is even further and you see from your ballistics software that you need 5.4 moa from your 100 yard zero to hit your target. All we have to do to figure out your mil dot hold over is take 5.4 and divide it by 3.6, because there are roughly (shortcut) 3.6 moa per mil; so (5.4 / 3.6) will equal 1.5, so hold 1.5 mils OVER, and send it……it’ll hit.
There are A LOT of shooters that will convert all their MOA hold over and under, to strictly mils. Many do this because it’s very easy for them to memorize that at 300 yards they need to hold 1 mil, or at 400 yards 1.5, etc. There is another trick that is pretty neat that you can do with mil dots, and if you know your data in MOA.
I’m going to borrow a webpage from Lindy from Sniper’s hide, because his page is where I first learned how to use different zeroes and hold over hold under. So this page is HIS, and I’m just using his data and example to further explain it to you here. The address of his page is this:
http://www.arcanamavens.com/LBSFiles...oads/Holdovers
The first thing that you need to understand is that you have one “true zero,” and the others are merely a reference to this zero. For simplification, we’ll use a 100 yard zero as our “true zero.” Your data for your dope should look something like this (from Lindy’s page):
Range MOA
100 0
200 2.0
300 5.0
400 8.0
500 11.5
600 16.0
700 21.0
Ok, so if we want our rifle to be zeroed at 400 yards, we need to dial into our scope 8.0 MOA, if you have ¼ moa clicks, this will be 32 clicks. So now, the rifle is zeroed in and will hit where the crosshairs are at, at 400 yards. So what do we do if we want to shoot at 100 yards using HOLD UNDER, because our rifle is zeroed at 400 yards? You take the adjustments in MOA and you subtract them. This means that we take the dope for where the target is at, 100 yards, and we subtract where our zero is at (now 400 yards). When we do this, we will take 0 MOA (100 yard target) and subtract 8.0 MOA (400 yard zero dope); when we do this it’s 0 – 8.0 = 8.0 . Now because our reticle is in MIL’s, we have to convert the MOA to Mil’s; we do this by dividing the MOA number by 3.438 (how many minutes are in a mil). When we do this we get 8.0/3.438 = 2.33. If you end up with a negative number, this means that you must hold UNDER the target, this seems logical because you are zeroed for a distance that is further away than what the target is, so if you held dead on, you would actually shoot OVER the target. So you will hold UNDER the target around 2.33 Mils. This means that you would hold 2 full mils and then just under halfway between the next dot.
With the same dope, what if I want to shoot at a target that is 500 yards away with our 400 yard zero, using only hold over? We take the dope to the target which is 11.5 MOA (at 500 yards) and subtract the dope for our zero, which is 8.0 MOA (for 400 yards). When we do this, we get 11.5 – 8.0 = +3.5. Now we need to convert these minutes to mils, which we do again by dividing by 3.438. When we do this, we will get 3.5/3.438 = 1.02 mils. Because the number is positive, this means that we need to hold OVER about 1 mil. This also seems to make sense because we are shooting at a target that is further away than what our rifle is zeroed for; if we shot at it without correcting, the bullet would impact low. (There are more examples of this on Lindy’s webpage if you’d like to see more illustration s and math of what’s going on. He lists the 500 yard example, but he actually uses the dope to be 12 MOA, instead of 11.5, so that’s why he comes up with a different hold.)
If you get your data in mils already, it makes using hold over and under direct, because you don’t have to divide anything and can just hold whatever the number is. The problem with this on a scope that adjusts with MOA is this; you can use hold over and under just fine, but if you want to dial into a new zero, you have to convert the mils back to MOA, so you know how many clicks to make.
These will probably never quite line up because you’re using mils to try to dial in on an MOA zero, it’ll be off a little bit. If you want to do it without having to convert back and forth, the easiest way is to use mil reticles with mil adjustments or moa reticles with moa adjustments. This is the problem that I was speaking about before that we have in the US…….we are using Mildot Reticles that have MOA adjustments, so we have to do an extra conversion. No worries though, it works perfectly fine.Last edited by Tomcat088; December 9th, 2008 at 12:59 AM.

December 9th, 2008, 12:56 AM #3
Re: Mildots, EVERYTHING you want to know.
Limitations of Milling
As you can see, there are LOTS of uses for mildots and the reticle. I want to mention a few things about ranging/milling with the reticle that can be limitations.
Because you are judging distance based on how an object appears, there are some visually factors that will affect the accuracy of this judgment. First off, if you can’t mil inside of .25 mils, you will have problems accurately ranging targets out to even 800 yards. If you are going to mil things out to 1,000 yards, it helps if you can mil all the way to .1 mils. The smaller that you are able to divide mils, then this will enable you to range distance more accurately.
I want to mention some things here that will make a target appear closer than it should be, or things that will make them appear farther than they should be. These do not come from my own person knowledge but books from military snipers. These things deal with the clarity of the target and its outline, the terrain, and light and atmosphere.
Objects will appear CLOSER than they actually are if most of the target is visible and offers a clear outline. This will depend on the color of the target and what the background of the target is. In terms of terrain, the target will appear closer if the shooter is looking at a target across a depression where most of the depression is hidden from view, when looking down on the target, and when looking straight down an open road, cleared path, etc. Targets will also look closer when you look over uniform surfaces like water, snow, desert and grain fields, and in bright light like when the sun is directly behind the shooter. Targets will also appear closer when they are in sharp contrast to the background or silhouetted. Targets will also appear closer in higher altitudes that have a clean atmosphere.
Targets will appear farther away than they actually are when only a small part of the target may be seen or is small in relation to surroundings. They will appear more distant when looking from across a depression and all of which is visible. Targets will also look more distance when looking from low ground up towards high ground. Targets will also appear more distant than they really are when field of vision is narrow…..such as confined streets, draws, and forest trails. Targets will appear farther than they really are in poor light such as dusk and dawn, and in weather conditions like rain, snow or fog, or when the sun is right in the shooter’s eyes. Targets will also look like they are more distant than they actually are when they are camouflaged, or they blend in well with background and terrain.
You will notice that when I’m talking about milling, we’re typically using HEIGHT of a target to mil with. It is possible to mil using the known width of targets, but it is not usually as accurate. The reason for this is that it is difficult to be directly lined up with a target; when you are not perfectly in line with a target it is not presenting its true width. When you are talking about milling objects that aren’t that wide to begin with, this introduces a margin of error into the calculation.
If you were shooting from a much higher or lower position than a target, milling with the height of the target can also be slightly compromised because you were not seeing the full height of the target. If you know both dimensions of the target and are straight on line with it, you can use milling both directions as a way to try to double check your milling.
Parallax Error
Another factor that will affect how you shoot and mil is “parallax error.” Parallax error can happen in all scopes that have variable magnification; on fixed power scopes you will NOT see this as a problem.
In simple terms, parallax error occurs because we are trying to take something that appears on multiple planes …(the reticle and target, and multiple lenses inside the scope, and focus)….and make it appear to be a single sight picture. You can determine if you have parallax error by getting your rifle perfectly still…getting a cheekweld… and then moving your head to one side or the other. If the reticle appears to float around or move, you are witnessing parallax error; if the reticle does not move when you do this, you have no parallax error.
Having a consistent cheek weld can aid in eliminating parallax error, but adjusting for the error is the best way to correct for it. Basically if the reticle is moving around, it’s hard to tell where the bullet is going to hit exactly because it doesn’t follow the reticle. Many scopes have “Side Focus” knobs or “Adjustable Objectives” that allow you to change the focus, these come in handy.
Most manufacturers will make the focus and parallax adjustment move together; this does NOT mean that you will have all the parallax error gone when the target is in clear focus. They are usually close, but sometimes where you have no parallax error, is when the target is slightly out of focus. If you must, it’s better to have zero parallax error and have a slightly out of focus target
Conclusion
I am no expert on any of this….. I’ve much less experience than many others that I know, but I do have some knowledge to share and I hope this has helped. I wanted to put this into a format that made it a bit easier to find MOST of it. If you’ve gotten to the end of this “article” of sorts, then I salute you for your persistence. If you are more curious about the system of mildots and how it came to be there are lots of other web pages on it, and this one is also pretty good:
http://www.boomershoot.org/general/TruthMilDots.htm
Realize that this data is not mine, so please do not give me credit for such; I’ve just accumulated all this over the years (in my head) from other forums, US Army and Marine manuals, etc. If you have any questions that I can maybe answer, feel free to ask them in this thread because others may benefit. If I was unclear about any of the math or calculations or anything else, please ask me to elaborate so I can correct and help make this difficult subject easier to read. If you have something that you’re nervous to post up, please feel free to PM me and I will also be happy to try to answer questions in PM. Remember not to get discouraged, milling accurately is something that takes a lot of practice and patience, but it can pay off. Be patient… learn to do the calculations… and even get a “mildot master” if you want something that doesn’t depend on batteries. (It is a slide chart of sorts that has data for target heights and mil measurements, and will give you distances.) Hope this helps and best of luck to you.
TomLast edited by Tomcat088; December 9th, 2008 at 12:59 AM.

December 9th, 2008, 09:07 AM #4

December 9th, 2008, 09:16 AM #5Grand Member
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Re: Mildots, EVERYTHING you want to know.
Great Information as always Tomcat
Sounds like my next Varmint scope might just have to have dots
ETA...gotta spread it, man
Glock Pistols.......So simple a Caveman could fix them!

December 9th, 2008, 03:18 PM #6
Re: Mildots, EVERYTHING you want to know.
Ya'll are very welcome, I hope that the information is useful and helps you progress with the mildot scopes. I know milddots seem a bit mystical or like some "sniper vodoo" to some people, lol, maybe this will help take some of that out. No worries mark, it got stickied, so it'll be up for a while, lol. I appreciate the thought though.

January 4th, 2009, 10:56 PM #7
Re: Mildots, EVERYTHING you want to know.
A very good, refreshing read. I had a lot of the information buried in amongst all the crap in my mind and all but forgot it. Thanks for helping me dig it out. Rep to you!

March 3rd, 2009, 10:30 AM #8
Re: Mildots, EVERYTHING you want to know.
I want to thank you Tomcat for taking the time to put this together, I found it to be great information and in great detail. I am just now starting to get an intrest in useing mildot scopes and this did help me. I will send rep's to you when it allows me to give some to you after I spread some around. Thanks again for this info.

March 3rd, 2009, 02:35 PM #9
Re: Mildots, EVERYTHING you want to know.
Thank you for letting me know that it was helpful and that you liked it. It did take quite a while to get it all put together in one place. Mildots can be a bit scary when you're first learning to use them, and they can be intimidating; but once you do learn them, it's a piece of cake and they're so helpful. I'll appreciate the rep, but if you forget, no worries, I'm just glad to hear that you found it helpful. Take care and if you have any questions or need any help, just drop me a PM or post it up here and I'll be happy to answer it.

March 3rd, 2009, 02:56 PM #10
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