In one sense, my article title of “How to use a mil dot scope for dummies” should read the opposite. This is because those who purchase a quality mil dot scope will certainly be making a very smart decision.
The real reason for the title is that there are lots of technical and mathematical articles available on mil dot scope use. Therefore, due to the complexity of the topic, this can make for some heavy reading. The intention here is to keep obscure words, meanings, and technical jargon to a minimum.
There is no doubt that getting the most from a mil dot scope will need patience and lots of practice. Having said that, it is a challenge that many shooters have already risen to.
So, if you are looking to reap the rewards in a variety of shooting disciplines, let’s get straight to it….
- 1 What Does “Mil-Dot” Stand for? It’s Not a Military Term!
- 2 First, The Mil
- 3 The Dot – Look to The Reticle
- 4 Using a Mil-Dot Scope
- 5 Where Does Your Mil Dot Reticle Sit?
- 6 Zeroing-in
- 7 Distance Estimation
- 8 Range Finding
- 9 Bullet Drop
- 10 Transitioning from MOA to Mil-Dot Scope Use
- 11 Features of a Mil Dot Scope
- 12 Looking for a Quality New Scope?
- 13 Final Thoughts
What Does “Mil-Dot” Stand for? It’s Not a Military Term!
Let’s start by clearing up what “Mil” and “Dot” actually mean.
First, The Mil
Although the abbreviation “Mil” often relates to “Military,” in this instance, it does not. An example of this more common abbreviation is one that most shooters will be familiar with: Mil-Std – this is the abbreviated form of “Military Standard” and refers to a set of tests performed on equipment and accessories.
These tests define whether or not the product in question is capable of withstanding expected harsh use that military personnel will put it through.
The “Mil” in “Mil Dot” stands for “Milliradian,” which is 1/1000th of a Radian. Still none the wiser? Nor was I! Anyway, radians basically measure an angle of distance that travels around a circle of any size. There are actually 6,283 milliradians (Mils) in a circle, although the U.S. Military begs to differ.
They calculate it as 6,400 milliradians in a circle. The reason for this dates right back to World War I. That was when the U.S. decided to replace degrees and minutes measurements they were using in artillery sights. This change resulted in them adopting the measuring system now known as the NATO Mil. However, for simplicity, they rounded the number of Mils per circle to 6,400.
The Dot – Look to The Reticle
Moving on to describe what the “Dot” in Mil-Dot stands for also needs to be understood. The Dot is not one Mil. It actually relates to Mil-Dot reticle measurements.
A standard Mil-Dot reticle design refers to a specific pattern of duplex crosshair reticles that come with four small (0.2 or 0.25 Mil diameter) dots positioned along each axis. The Mil measurement is the distance between the centers of any two adjacent dots. This angular measurement widens with distance.
This dot arrangement allows users to estimate range. Experienced Mil-Dot reticle users have the ability to measure the range of any known-size object as well as determining object sizes at known distances. As for bullet drop and wind drift compensation, this can also be achieved if the target distance is known.
Don’t mix them up…
For shooters researching Mil-Dot reticles, it is important not to confuse them with BDC (Bullet Drop Compensating) reticles. This is because BDC reticles work by compensating for the effect of gravity on a bullet at given/known distances. Mil-Dot reticles give the ability to estimate an approximate hold-over or perform scope elevation adjustments when weapon and ammunition ballistics are known.
Examples of One Mil imperial measurements with Mil-Dot reticles are One mil at 100 yards equals 3.6-inches – One mil at 1,000 yards will have widened 10x to 36-inches. When calculating the distance from dot-to-dot in 100 yard increments, you will find it increases by 3.6-inches for every 100 yards.
So, 100 yards = 3.6-inches, 200 yards = 7.2-inches, 300 yards = 10.8-inches, 400 yards = 14.4-inches, 500 yards = 18.00-inches and so on until you reach 1,000 yards = 36.0-inches
Using a Mil-Dot Scope
The first thing to be said is that shooters should familiarize themselves with the decimal metric system of measurements. This is different from the U.S. Imperial measurement system that we all know and love. The decimal system makes conversions and calculations far easier.
Most Mil-Dot scopes come with .1 MRAD or 1/10th Milliradian adjustments per click. This means you can divide the space between each Mil Dot 10x. With markings of .1 MRAD per click, Mil-based reticles can be broken down into 10ths. This allows for accurate reticle use while matching the adjustments on the scope.
Leupold uses .05 click adjustments, but that is the exception rather than the rule.
For the purpose of this explanation, .1 MRAD (1/10th) click adjustments will be used.
Shooters who intend to constantly swap and compare decimal and imperial measurements will find lots of math calculation tables available. The issue here is that such conversions and comparisons can become quite confusing.
To begin with, the thinking should be that a Mil is a Mil whether you hold or adjust and no matter how close or far (distance). Once you become familiar with your Mil-Dot scope, you can then study decimal against imperial measurement comparisons.
Where Does Your Mil Dot Reticle Sit?
Mil-Dot scopes come with reticles either in the FFP (First Focal Plane) or the SFP (Second Focal Plane). Where yours sits is a very important factor. Depending upon your shooting application, both have advantages and disadvantages. However, the FFP reticle certainly offers more when it comes to sub tensions and therefore is often the preferred option.
This is because FFP reticle sub tensions will be correct on every power setting within the scope’s variable magnification range. Use of an FFP reticle will increase and decrease in size as you increase or decrease magnification and will remain consistent at any power level.
This means it can be used to determine distance, bullet drop and size no matter what magnification setting you are one.
With an SFP scope…
Here the reticle tends to correctly subtend at only one power setting. While this is usually its highest setting, you should check details with the manufacturer or in your user handbook. This means that reticle accuracy of 1 Mil will only equal 1 Mil at the manufacturer’s defined setting.
So, unless you are on the manufacturer’s specified magnification setting, you will not be able to use an SFP Mil-Dot reticle for finding range, estimating size, or for BDC (Bullet Drop Compensation).
Once you have mounted your scope, it is time to complete the zeroing-in. To do this, you should shoot a three-shot group aiming for the target center. Then look through the scope at this group to see what adjustments are needed.
You should not be thinking in imperial measurement terms by trying to convert or work out what 1 MRAD means at 100 yards in inches. That is not necessary. What is necessary is for you to learn exactly how to read the reticle. This means understanding the Mil-Dot reticle to the 1/10th of a Mil. By doing so, you will then make adjustments up/down, left/right in 10ths to get your next group on the center target.
If a shot ends up 1 Mil High and 2 Mils Left of target, you will see this shot placement on your sight. You will then know that click correction adjustments need to be 1 Mil Down and 2 Mils Right.
What also needs remembering is that you are breaking up the space between reticle centers and Mil-Dot center, not to the edge (which also has a value). Mil Dot reticle design varies depending upon the manufacturer, but, as mentioned, most are .2 Mils wide.
However, check this because some are .25 Mils wide, and as for some reticles with Hash Mark design, it will be even less. This is because you need to account for reticle thickness when reading a Mil-based scope.
As with lots of firearms procedures, there are other ways to zero in. If you have a shooting buddy who is already using a Mil-Dot scope, ask them about their method. You could also check the instruction manual or scope manufacturers’ websites for their recommended zeroing-in process.
The majority of hunters now use laser rangefinders in order to estimate target distance. This is certainly the most effective method. However, in the event your rangefinder stops functioning, a Mil-Dot scope can come to the rescue.
The formula to use in metric measurements is:
Target size in cm x 10 (this is a constant multiplication used for calculating distance in meters) / Mil size = The estimated distance (in meters).
For example, if your target is 38.1 cm (centimeters) tall and its reticle spread is almost 1.5 Mil your calculation would be: (38.1 cm x 10) / 1.5 = 381 / 1.5 = 254 meters.
If using the imperial measurement system:
Target size in inches x 27.778 (this is a constant multiplication used for calculating distance in yards) / mil size = The estimated distance (in yards).
For example, if your target is 15-inches tall and its reticle spread is almost 1.5 mil, your calculation would be: (15 x 27.778) / 1.5 = 416.67 / 1.5 = 277.78 yards.
Shooters who want to familiarize themselves with the metric system should stick with the first calculation formula. However, it is possible to interchange formulas by converting cm into inches or inches into cm.
When you have a specified target range, it is necessary to go through all calculations to ensure the perfect shot. Most shooters will have loads and relevant information written down. The important thing to remember is the ballistic impact and wind speed to ensure the perfect shot.
As has already been mentioned, Mil-Dot scopes capture the angular measurement (not the linear measurement). As a standard evaluation, this is 1/6400th of a circle. That means a milliradian equals 1 meter at 1,000 meters and 1 yard at 1,000 yards.
The formula for finding the range with a Mil-Dot reticle scope in meters is:
The target width or height in meters x 1,000 / The target width or height in Mils = The Range (in meters)
This formula is exactly the same if you are measuring in yards. But all measurements should be in yards, not meters.
For example, if the target object is 2 meters or 2 yards in height and it covers 1.5 Mils in length, the actual range calculation would be 2 x 1000 / 1.5 = 1,333.3 meters/yards.
Bullet drop is used to show the exact dropping limit at a certain range or distance. To achieve precise aiming and hitting points at the drop rate, it is necessary to know your rifle and ballistic effects. Rather than calculating this yourself, there are lots of online calculators available that give the precise data for bullet drop.
But, let’s give some brief insight on bullet drop statistics:
You will have no concerns if shooting at 100 meters or 100 yards. However, as your distance increases, bullet drop and Mil adjustments come into play.
Here are two examples of distance in meters, bullet drop in centimeters, and Mil adjustment necessary:
Distance: 200 meters – Bullet drop = 14 centimeters – Mil adjustment = 0.7
Distance: 500 meters – Bullet drop = 242.3 centimeters – Mil adjustment = 4.8
Taking the same two examples but in yards, inches, and Mil adjustment:
Distance: 200 yards – Bullet drop = 4.2 inches – Mil adjustment = 0.6
Distance: 500 yards – Bullet drop = 73.0 inches – Mil adjustment = 4.1
Transitioning from MOA to Mil-Dot Scope Use
There is no disguising the fact that moving from MOA scope use and calculations to Mil-Dot can be a challenge. This is largely down to the different measurement calculations. However, with patience and practice, this is achievable.
When Mil-Dot scopes are used to their full potential, they can bring more to your shooting experience. In this respect, tactical and long-distance shooters, in particular, will see these benefits.
Experienced MOA scope users who are considering moving to Mil-Dot scope use will have a valid concern. This relates to distance shooting and the fact they have all of their DOPE (Data On Personal Equipment) details in MOA format.
Transitioning to Mil-Dot use means they need this data to read in meters and not in already calculated yards. Thankfully there is a conversion formula that makes the transition with ease and accuracy.
To convert MOA values to Mils, divide MOA by 3.438 – This will give you the Mils data required.
As an example, you are currently using 8 MOA at 400 yards. Using the above calculation would mean you should use 2.3 Mils over the same distance.
It will be far more convenient for you to complete these calculations before you hit the range. By doing so, you will have the Mil data on your range card. This will allow you to refer to it as you normally would with your MOA data. The difference being that you are used to reading your DOPE from 0 to around 38 MOA; this can now be done by only counting to 12 Mils.
As already mentioned, when it comes to windage conversion data and ballistic calculators, there is a good choice of online conversion charts and calculators available.
Features of a Mil Dot Scope
MOA (Minute Of Angle) scopes have been (and still are) the preferred choice for U.S. civilian shooters. However, Mil-Dot scopes (also known as MRAD – Mil-Rad scopes) are steadily gaining in popularity. As previously mentioned, tactical shooters and those into long-range competition will find particular benefits.
Quality Mil-Dot scopes are built to last and offer rugged durability. This means they will perform in harsh environments and keep coming back for more. They also include quality glass to ensure crisp and clear image views over variable magnification ranges. At the top end of the magnification range, they offer more than enough power to please long-distance shooters.
Looking for a Quality New Scope?
Then check out our reviews of the Best Mil Dot Scopes, the Best Long Range Scopes under 1000 Dollars, the Best Deer Hunting Scopes, the Best Long Range Rifle Scopes, or the Best AR10 Scopes you can buy in 2021.
Firearms enthusiasts should always be looking to improve their knowledge and skills. Mastering a Mil-Dot scope certainly comes in that category. While they may not be for everyone, tactical shooters and hunters looking to get rapid follow-up shots off will certainly benefit. As for those long-distance competition shooters, that all-important accuracy advantage can be yours.
The actual learning curve is not as steep as many may think. There will also be no concern for shooters who already have precious DOPE detail in MOA format. They can rest assured that there is a quick and easy formula that accurately converts MOA data into Mil-Dot data.
In summing up, to this shooter’s mind, Mil-Dot scopes are well worth the investment. This is both in terms of purchase price and as a way of increasing your firearms experience.
Happy and safe shooting.