There are a lot of articles and forum threads out there comparing MIL and MOA, but most either aren’t objective or they’re overly complex. I’ll try to avoid both of those pitfalls in this article.
Executive Summary
A few months ago I asked Bryan Litz whether he personally used MIL or MOA. Bryan is an expert among experts in the shooting community, and after reading his books I’ve gained a respect for his scientific approach to decisions like this. His response was so concise and objective, I thought it could serve as the executive summary for this whole comparison:
“You can’t really go wrong with either (MIL or MOA). They’re both equally effective, it comes down to how well you know the system. If you’re comfortable with MOA, I wouldn’t recommend switching to MIL. I have a few MIL scopes but primarily because they’re on rifles used for military evaluation projects, and that community is now mostly converted to MILS, so when in Rome…
So if you have a hunting buddy that you want to be on the same page with, that might be a factor. But for your own use, neither has an inherent advantage.”
– Bryan Litz, Author of Applied Ballistics for Long Range Shooting & Chief Ballistician at Berger Bullets
There are a handful of minor differences/trade-offs between MIL & MOA, but there are no inherent advantage to either system. Most people blow the small differences WAY out of proportion. So if you are like I was and stressing about what to go with … relax, neither is the wrong decision. Here are the biggest differences and things to keep in mind. The rest of the article will expand on these in more detail:
- 1/4 MOA adjustments are slightly more precise than 1/10 MIL
- MIL values are slightly easier to communicate
- If you think in yards/inches the math for range estimation is easier with MOA. If you think in meters/cm the math is easier with MIL.
- If you have a friend that is already using one, there is some advantage to being on the same system.
- Around 90% of the pros use MIL
- More product options in MIL
- Whatever you decide, go with matching turret/reticle (i.e. MIL/MIL or MOA/MOA)
The Factual Differences
There are only a couple differences between the systems that have much merit. They are very slight, and barely worth mentioning.
1/4 MOA Is Slightly More Precise Than 1/10 MIL
The most common adjustments are 1/4 MOA or 1/10 MIL. Technically, 1/4 MOA clicks provide a little finer adjustments than 1/10 MIL. This difference is very slight and it’d be hard to claim you could “shoot between those numbers.” It only equates to 0.1” difference in adjustments at 100 yards or 1” of at 1,000 yards, and there are very few shooters who could hold well enough to notice that difference (or isolate it to that single factor). I can’t.
If finer is better, why not go to 1/8 MOA clicks? Some scopes have that, but most long-range shooters feel like that is too fine. In fact, at the 2013 Steel Safari competition Ray Sanchez said he actually thinks 1/4 MOA is too fine, and actually prefers 1/2 MOA adjustments on his scopes. Ray is a very accomplished shooter, having won national long-range shooting competitions and is well respected in the shooting community. He thought for practical long-range shooting he would rather be able to dial quickly (15 MOA of adjustment is 60 clicks with 1/4 MOA adjustments, but only 30 with 1/2 MOA), and his experience has taught him that having adjustments as fine as 1/4 MOA just isn’t as important as the rest of the things that go into executing a good shot. I can’t say I totally agree with him but there does seem to be a balance point there somewhere, between too fine of an adjustment but fine enough to dial in the spot you want to hit. Most shooters agree that 1/4 MOA or 1/10 MIL are both right around that sweet spot, which is evident in the scopes used by the pros.
MIL Values Are Slightly Easier To Communicate
You can see in the range card examples below, 1/4 MOA adjustments take up more room and are a little harder to read than 1/10 MIL adjustments. The adjustment for 725 yards is “22.75” MOA (4 digits), or “6.6” MIL (2 digits). That is essentially the same angular adjustment (dope cards are both for the same ballistics), but MILs are larger units so they are represented by significantly smaller values than MOA. Also units in 10ths fit our numerical system (base 10) more naturally than fractional units. Not only does that make a range card simpler and quicker to read, it also is slightly easier to communicate elevation values to a partner. It’s just easier to process “6.6” instead of “22.75”.
How Do You Naturally Think?
If you naturally think & talk in terms of meters and centimeters, the math for range estimation is easier with a MIL system. But if you naturally think & talk in terms of yards and inches, the math is easier with a MOA system. If you don’t plan to do range estimation with your scope (which few do), then both are equally effective.
Here are a couple questions to help you figure out what you naturally think in:
- When asked how far away a target is, would you answer in yards or meters?
- When asked how wide a target is, would you answer in inches or centimeters?
- Is your rangefinder set to give units in yards or meters?
- Is your dope card in yards or meters?
If you typically think in yards & inches (i.e. U.S. Standard Units), that doesn’t mean you can’t go MIL. But if you are around guys like Todd Hodnett or members of the military that use that system … you will quickly notice they talk in terms of meters (i.e. metric units). Overtime you can train your brain to think in metric, but it is almost like learning to speak another language. It just takes time/discipline and/or immersion in the new system to make the switch.
If you try to do range estimation in yards with a MIL based system, the math will be more difficult. I’ve provided several examples that illustrate this at the end of this article. It is actually too difficult for a lot of people to do in their head, so they end up relying on an index card filled with sizes of targets in inches, the measured size in MILS and the range those equate to. In fact there are even many tools out there to address this exact problem (e.g. Whiz Wheel, Mildot Master Slide Rule). You can avoid needing to carry something like that altogether if you simply stick to doing range estimation in meters with a MIL based system, and in yards with an MOA based system.
Like Bryan Litz mentioned, if you have a friend that you shoot with a lot that has already committed to either a MIL or MOA system, there is some advantage to you both being on the same page. I have friends that shoot both (2 of us MIL, and 2 of us MOA) … and I can testify firsthand that it can get confusing when asking what someone’s wind hold was. If you compete as a team, then the communication you need to have to compete makes it virtually a must to use the same system.
What Do the Pro’s Use?
That’s right, 46 people in the 2013 Precision Rifle Series said they used a MIL based reticle, and only 3 said they use a MOA based reticle. 7 said they used a reticle that is available in both MIL & MOA, so I threw those out because I couldn’t say with certainty which camp they fell in. But a 49 person sample size containing people willing to compete in up to 15 national matches each year can be very telling.
This does NOT mean MIL is better. It just means MIL based scopes are more popular, even among the top 1% of shooters out there. It also might be a chicken and egg question or even almost a self-fulfilling prophecy, because high-end MIL scopes are more readily available.
Military & Manufacturer Influence
The popularity of the MIL system is undoubtedly heavily influenced by the military standardizing on the MIL system. When the military standardizes on something, it suddenly becomes very popular in the civilian world as well (sometimes regardless of how it compares to other options available). For example, look at the popularity of the civilian equivalent of NATO-based cartridges like the 223 Rem, 308 Win, 300 Win Mag, 338 Lapua, and 50 Cal. There may be other cartridges that are ballistically superior to some of those rounds … but that short list still continues to outsell every other cartridge year over year.
Many manufacturers choose to focus on MIL-based systems because they are competing (or hoping) for military contracts. And since the two systems are so similar, and there isn’t an inherent advantage to either … why have to tool your entire assembly line to offer both? Also since there doesn’t appear to as high of demand for MOA based systems, companies may make a business decision to only offer MIL based systems to reduce their internal complexity and increase efficiency. Many of the high-end scopes are made by European companies like Schmidt & Bender, and virtually every country outside the U.S. has switched completely to the metric system. So it may not be as big of a sacrifice in their eyes to only offer MIL based systems.
The fact remains, whatever the reason, that there are more products based on MIL than MOA. For example, try to find a spotting scope with a MOA based reticle (used for ranging targets). I personally looked a couple months ago, and slowly became convinced they simply don’t exist (at least at that time).
Matching Reticle & Turrets
Whatever you decide, don’t mix reticle & turrets of different units. Many entry-level scopes may have a mildot reticle (MIL based), but the turret adjustments are in 1/4 MOA clicks. That doesn’t make a lot of sense, and can limit how quickly you can make 2nd round corrections. If you are using a reticle/turret system that is either MIL/MIL or MOA/MOA, and you see your 1st bullet splash impacted low, you can quickly measure how far low using your reticle and dial that extra adjustment for a speedy follow-up shot. For example if it was 1 MOA or even 1 MIL low, just turn your knob an extra 1 MOA or 1 MIL respectively and you should have a second round hit. You could alternatively hold high by whatever amount you measured instead of dialing it and avoid the conversion, but I like to know what the correct dope should have been so next time I can dial it in and get a 1st shot hit.
When you mix the units you are essentially trying to live with one foot in each camp, and it can make life harder than it needs to be. For example, if you had a scope with a mildot reticle and MOA adjustments and saw the bullet splash was 1.5 mils low. You would have to do some math to figure out what the equivalent adjustment would be in MOA. The math below would indicate you need to dial an additional 5.25 MOA (if you were using 1/4 MOA clicks).
I have a very smart friend that is an accomplished long-range shooter, and he actually prefers a MIL reticle with MOA turrets. It blew my mind when he said that, but he prefers to talk about wind holds in mils because that is what most other people are talking in. But he prefers the finer adjustments 1/4 MOA clicks provide, and to him the dope card is just a number he turns his scope turret to … he doesn’t care if it is MOA or MIL. So on his dope card, his elevation adjustments are in MOA and his wind adjustments are in MIL. I’ve had to do that for one of my scopes in the past, and I personally didn’t like it. But there are at least a few opinions out there on this.
Range Estimation Math Examples
The examples below illustrate how easy it is to use the MOA system to do range estimation in yards, and how well the MIL system can do range estimation in meters. There are also some examples that illustrate how difficult the math can be if you try mix the metric/standard systems by trying to use the MIL system to do range estimation in yards. Here are the range estimation formulas we’ll use for these examples:
You can see in the formulas that we have to multiple some things by 10 or 100 … but when you mix yards and MILS you end up with strange constants like 27.8 to account the necessary conversions between the standard and metric systems. Some people even show that number to be 27.778, but that level of precision just isn’t necessary for range estimation when using small arms. Multiplying by 10 or 100 is simple compared to multiplying things by 27.8. Even the best math whiz would have difficulty doing this level of math in the field under any type of stress or time constraint.
MOA Example 1: Simplest Math Scenario
Using your MOA reticle, you measure Target A to be 2.0 MOA wide. You know the actual target is 18” wide, and you want to find the range in yards.
MOA Example 2: Complex Math Scenario
Using your MOA reticle, you measure Target A to be 3.5 MOA wide. You know the actual target is 18” wide, and you want to find the range in yards.
MIL Example 1: Simplest Math Scenario
Using your MIL reticle, you measure Target A to be 1 MIL wide. You know the actual target is 18” wide, and you want to find the range in yards.
MIL Example 2: Complex Math Scenario
Using your MIL reticle, you measure Target A to be 0.7 MIL wide. You know the actual target is 18” wide, and you want to find the range in yards.
MIL Example 3: Sticking with Metric (Size in CM & Range in Meters)
Using your MIL reticle, you measure Target B to be 0.4 MIL wide. You know the actual target is 30 cm wide, and you want to find the range in meters.
People Who Liked This Post Also Read …
Best Rifle Scope – What The Pros Use: This post shows the scopes and reticles the best precision rifle shooters in the country are using. It is based on what the top 50 long-range shooters brought with them to the most recent Precision Rifle Series (PRS) Finale. Target engagements for a PRS match can range from 25 to 1,200+ yards, but there is definitely a focus on the “precision” rifle part regardless of the range. This is some unique “hard data” about what the optics the pros are using.
Best Long-Range Scope: Buyers Guide & Features To Look For: Advertising around long-range scopes can be misleading. This post boils it all down to the biggest features you should focus on when comparing long-range scopes. This guide explains what all the different features mean, gives you an idea of which are more important important, and helps you filter out some of the marketing noise when researching rifle scopes. I also make specific recommendations for different price points, to help you get the best rifle scope for the money.
I totally disagree that 1/4 MOA clicks are adequate for long range shooting. Most F-Class shooters (myself included) need the precision of 1/8 minute clicks. This is critical when you want elevation spot on and hold off for wind.
Yes sir, valid point. I could see 1/8 MOA adjustments being ideal for benchrest or F-Class use. My primary focus is on long-range hunting, extended long range plinking (up to 2000 yards), and practical/tactical competitions. In those cases, it may be too fine. But ultimately, it comes down to personal preference. This is one of those times were there isn’t a wrong answer, just whatever works for you.
Thanks for a well-written and informative article. I’m an American living and hunting in Sweden and this is a topical issue as my local hunting buddy and I think in different measurement standards.
-James
James, this is becoming an age-old debate that virtually everyone (at least every American shooter) has been part of. It seems like houses have been divided over this argument! I just attempted to bring some objectivity to this heated topic. Glad it helped!
Cal, Have you tried this formula for ranging a target with a Mil reticle?
(Target size in YARDS x 1,000) / Target size in Mils = Range in yards. It is a bit easier than that other formula you used as an example.
Hey Tony, thanks for sharing! I’m not sure I’ve seen that formula. It seems to work, and certainly seems a easier for larger targets. It may be still make the math tough in some scenarios, like an 8″ or 10″ target (0.2222 yards and 0.2778 yards respectively). I guess you just round, but that could lead to range precision issues.
But honestly, I don’t find myself milling targets a lot. I’m sure there are guys out there that still do it, but I just don’t know any. I carry a rangefinder. So I don’t find myself doing a lot of math (in yards or meters) in the field. I’d expect there were more shooters who fall into that camp than guys who mil targets. But that’s a guess. I’ve heard some guys claim milling was more accurate, and it might be in some scenarios.
Thanks again for sharing! I’m always open for a better way to do things.
THAT’S exactly what I was going to say. The 27.8 number is because you mesure your target in inches and you want to end up with yards. By the way milrad is NOT a metric system, but it is easy to compare it with that system. Milrad ( comes from milli radian ) is based on 1 / 1000 of radian. So, it is easier to calculate even with SAE system. Lets say for example that 36 inches at 1000 yards is the sams as 3.6 inches at 100 yards for 1 milrad. (Or 1 mildot).
Regardless of the semantics, at the end of the day they’re both just angular units of measure. There is NO inherent advantage to either system.
Thanks,
Cal
But there is an advantage to the mil system. Especially once you find out that the formula for moa ranging in yards is not correct. It is actually (size in inches)/(moa size) * 95.5 = (range in yards)
Hey Andrew,
It’s great when you realize that the numbers others have told us are not quite correct, and therefore you begin reaching out for greater precision in trying to strip-away the mud from the equations. Actually, the exact number is 95.28, not 95.5. All errors compound. At 2,101 yards, you would be out 1″ from reality, right out of the gate, before you did a single physical thing, before nature conspired against you with other factors, and that is something no one can afford if they’re in the game to master it.
There is no ‘natural thinking’; we are to be the masters of our own minds, we dictate what shall be done (or not) with the power of it; it is called the will, and if fully invoked can cause the near-impossible to happen. From Newton to Navy SEAL’s… these people force the mind to be strict, and obedient. Others may simply call this “passion”, but it is harsher, cleaner, and stronger, because it is pure.
PLEASE… see my fully extrapolated post of September 19, 2015 (way down, presently third from the bottom) for all the errors in addressing MIL versus MOA. Once you see the actual numbers unfold, you’ll realize purity is everything when it comes to mathematics, and the confusion created was generated by ourselves, not the ‘real’ math. But we can change. We didn’t get to the Moon (talk about ballistics equations!) by using ‘sorta the right numbers’. There can only be one “Deadliest marksman on the planet”, only one “Most precise shooter in the world”, and to this day, there has only been one nation to actually put men on the Moon (6 times!). Using primarily the same factors, the first one being the purity of mathematics, they did what all great shooters are attempting to do: Perfect deliver to the target of a projectile… a mathematical/ physics impacted/ human interactive event.
One down (the discipline of mathematics [especially geometry]), two to go (physics of forces, and the shooter’s concentration at the moment of trigger release on a precision instrument).
Richard,
As a scientist I fully understand that math is extremely important and it has a huge part to play in shooting. However, because I am an engineer and not a physicists, I also understand that most people don’t fall into the categories that you have layed out. Most shooters wouldn’t ever shoot at 2000 yards seriously and even less will attempt to range something that far with an optic.
The point of my earlier comment was mainly to show how the author was being sort of disingenuous. The authors premis is that moa ranging is easier when working with English units of measure. I was trying to show that the formula used to come to the conclusion that was reached was done by rounding.
I think that two other things should have been considered before that conclusion was reached. The first is that no one is going to be doing this math in their head unless the numbers work out, a calculator is a must. The second is that the same sort of easy math can come out of a mil equation of you are willing to convert inches to yards before using the formula.
With all that said I do understand and support your point of being precise and accurate when the situation calls for it.
Best regards.
Andrew
Alright guys. That’s enough on the argument about milling long range targets for range estimation. It’s impossible to do that with the accuracy you need. If you don’t believe me, go look at the empirical data on this. I did a post on it that is 100% objective and shows how your probability of hitting a target is extremely limited even for the best military snipers milling a target for range estimation. The probability falls well below 50% hits very quickly. In the day of laser rangefinders, milling a target for range estimation is an academic exercise or a “Plan Z” at best, at least when it comes to long-range shots.
How Much Does Accurate Ranging Matter?
I won’t approve any more comments related to milling targets for range estimation. It seems lots of people want to argue about it, but it’s not a helpful conversation.
Thanks,
Cal
How do you tell if the reticle is Mil or MOA?
That’s a good question. You can’t really tell by just looking at the hash marks, but there are usually number index marks. MOA will always be a much larger number than mils, because 1 mil = 3.38 MOA. Here is a link to two Nightforce reticles that are very similar, the MIL-R and the MOAR … except of course one is MIL and the other is MOA. Every mark on the mil based reticle is 0.5 mils, and the number indexes printed on the reticle are relatively small number (2 & 4 mils). On the MOA-based reticle, every mark is 1 MOA, and the numbers indexes are much larger (10 & 20 mils). So if you have numbers on the reticle, usually if they’re double-digit it’s MOA.
If you don’t have number indexes printed on the reticle, it’s probably a mil-based scope. Not only are they more prevalent, but the dots (or hash marks) are just understood to be 1, 2, 3, 4 mils and so on. So it’s common on mil-based scopes to not include any number indexes. But, you can double-check that by drawing a line that is exactly 3.6″ on a target and set it at 100 yards, which is what 1 mil should be at that distance. Look through the reticle and see if that aligns with the marks. If it does, you’re mils. If it doesn’t you’re likely MOA.
Thanks,
Cal
Well now I’m really confused! You said to make sure the reticle & turret are both either MIL or MOA. No one seems to know how to tell the difference on the reticle. I would need to know before buying, so drawing lines on cardboard @ 100 yds isn’t going to work.
Ha! Sorry, for the confusion. I thought you had a scope and you didn’t know if it was in mils or MOA. So sorry.
Every reputable scope manufacturer I’ve ever seen will somehow indicate whether the reticle is mil-based or MOA-based, along with what the turret click values are. But you may have to dig, or at least know what to look for.
Here is a screenshot from EuroOptic.com that shows what I’m suggesting you avoid. This scope has MOA-based turret clicks, but the reticle is in MILS. You either want a MIL-based reticle and MIL-based turret adjustments, or a MOA-based reticle with MOA-based turret adjustments. You can see this example mixes the two. You essentially don’t want the words MIL and MOA to both appear in the product specs.
If you aren’t sure if the reticle is in MILS or MOA, visit the manufacturers website. One of the reasons I like EuroOptic.com, is because they usually have a link to the reticle subtension diagrams right there for you. You can see in the screenshot under the photo of the scope there is a link for “Nightforce Mil-Dot Reticle Subtensions”. That will tell you whether the reticle units are in mils or MOA. Of course, you could always go to Nightforces website and they provide that info there as well. Here is an example of how they publish that data: http://nightforceoptics.com/pdf/ReticleManual.pdf. But every manufacturer has something similar. If they don’t … I’d run. They are missing some of the fundamentals, and I bet their product is too.
Oh, and one more tip … Shooter’s MOA (aka 1/4″ clicks at 100 yards) is NOT the same thing as MOA. Just avoid Shooters MOA all together. It’s intended for hunters … not precision rifle shooters.
Thanks,
Cal
And if the spec says that the adjustments are 0.1 mrad … that is mil-based. MIL and MRAD both stand for milliradian.
Thanks,
Cal
This site is very very good for those of us that are considering purchasing long distance shooting gear, but don’t really have any experience. I know it is a nit, but in checking your distance equations using MIL and MOA, I find the MIL equations to be correct, however I believe the MOA equation should use 95.493 rather than 100. At 1000 yds, it is only a 45 yard difference in distance. As you say, since most are using range finders these days, it may be superfluous.
Again, great job on the site. It is most helpful !!
Thanks, Jim.
Cal, thanks for the great article. By necessity I came up with a way to use MILS and Yards/Inches in an easy way:
Range in Yards = (Target Size in Inches + 10%) x 25 / MILS
This gives some nice numbers for targets of 9″ (head), 18″ (shoulders), 36″ (belt up), 72″ (height) (rounded with +10% as 10″, 20″, 40″, 80″).
In addition, you can also quickly convert to Meters by doing -10% of the Yards.
Thanks for sharing.
I agree with you! As long as you buy a scope that has the same “system” with the reticle v/s the tourets. I bought myself a milrad/millrad type scope while one of my friend bought a scope with millrad reticule v/s MOA tourets. Believe me, it’s not easy to work with… but he bought a “price”.
One MOA is about one inch at 100 yards. But the true value is 1.0472 inches, an increase of 4.72%. That inaccuracy will adversely affect range estimation. A 20 inch target measuring 8 moa is not 250 yards away, but 238.7 yards away (error of just over 10 yards). The error at 20 inches and 4 moa is over 22 yards (477.5 instead of 500 yds). By comparison, mils is exact. A 500 millimeter target measuring 2 mils is 250 meters away. So the mil-dot system is more accurate.
Thanks, MRoy. That is certainly all true. However, there honestly aren’t many guys milling targets for range estimation on small targets at long-range. I’ve actually never seen one. I’m not saying it isn’t good to have that skill in case electronic rangefinders fail, but lots of guys get really worked up about the precision of milling targets like what you’re talking about … when in reality, milling targets is already very prone to error. Your reticle just isn’t a fine enough ruler relative to the tiny angles we’re dealing with to give you a good range estimate.
I touch on this in more detail in a post last week: How Much Does Accurate Ranging Matter?
A marine scout sniper said “Most experienced snipers can measure down to five hundredths of a mil or 0.05.” I really analyzed that in the post, and that could easily cause you to have up to 45 yards of error. There are lots of photos and examples in that post to help illustrate the problem with that approach. If you’re shooting a man-size target or a vehicle … it might not matter. However, if you’re trying to shoot a 1-2 MOA target … it seems very unlikely you’d be able to get a 1st round hit if you were estimating the range by milling the target.
I don’t want to get in an argument over this, but have noticed how easy it is for people to get caught up in the details and not realize that isn’t a situation you’d probably ever find yourself in.
Thanks,
Cal
Well…… when coming in from an academic’s point of view, there is a reason the rest of the world went to metric…. accuracy, ease, consistency. Enough said.
Wow.
There is nothing about the mil system that makes it inherently more “accurate” or “consistent” than MOA. You might could make an argument that the metric system in general is easier to use (i.e. centimeters, meters, kilometers), because it features a a standard set of prefixes in powers of ten. But, just throwing a claim out there like it being more “accurate” or “consistent” in a conversation about Mils vs MOA is an overly dogmatic view, regardless of whether you came from the academic community or not. It’s exactly the type of view that causes so much confusion on this topic. They’re both simply angular units of measure, with slightly different scales. If you like mils better, great. But it doesn’t mean MOA is less “accurate” or “consistent”. It simply means you prefer mils. Nothing more. It might be better if everyone in the world got on one system, but that doesn’t mean people are wrong for using MOA … just because you picked mils.
Enough said.
Cal
There’s nothing inherently metric about mils. They key point about mils is that the ratio between something 1 mil high in your scope and the range to that object is 1:1000. If the object is 1 yard tall, it’s 1,000 yards away. If it’s 1 inch tall, it’s 1,000 inches away. If it’s 1 meter tall, it’s 1,000 meters away. If it’s 1 cubit tall, it’s 1,000 cubits away. It doesn’t matter what units you use; the ratio is always 1:1000.
The corresponding ratio for MOA is 3,438.
The complication comes in when you layer in a unit conversion on top of whichever ratio you’re using. If, for instance, you want to measure the target in inches and the range in yards, then you need to throw a factor of 1/36 (36 inches to a yard) in there. 1000/36 = 27.8, which is where that number comes from in the formula you cite; 3438/36 = 95.5, which isn’t much easier but can be rounded to 100 without losing too much accuracy. That’s the only reason the MOA formula is easier; but it’s easier ONLY if you’re using inches and yards; with any other set of units, you’d be trying to divide something into 3,438 in your head, and good luck with that.
Whereas the mil formula starts out easier, because it’s based on the ratio 1:1000; any unit conversion you need to do after that is inherent in whatever system of distance units you use, not mil vs MOA. Metric has easier conversions — they’re all powers of 10 — so if you’re going to, say, measure in centimeters and range in meters, then it ends up being easier to do in your head.
But if you’re able to measure the target and range in the same units, then the mil formula is straightforward no matter what units they are — metric, English, Martian, it doesn’t matter.
Good point, Ross. Seems like sound logic to me.
I honestly don’t find myself ever milling targets (outside of the one day in a long-range class that taught me how to do it). This seems like something a lot of guys get hung up on (or at least like to argue about) … but ultimately, I’m not sure it matters. I can see how military personnel might need to know how to do it in case electronics fail and there is a life-threatening situation, but I just haven’t ever seen someone mil a target in any kind of competition or just out shooting with friends. I did a data-driven analysis on the impact ranging error introduced by milling targets has on long-range shots. Your hit probability falls to nothing quickly.
How Much Does Accurate Ranging Matter?
I do appreciate the comment. You definitely presented that in a really simple way, which I can appreciate.
Thanks,
Cal
I know this is an old post but maybe I will get a answer in the ranging formula using moa, some use 95.5 some use 100 , so what does this number represent , why times 100
I’m not sure, Frank. It probably has to do with unit conversion from MOA and inches. But honestly, I wouldn’t worry about it. In the age of the laser rangefinder, estimating range by using your reticle to measure the target has become as important as knowing how to use a hand crank to start a car. The military still teaches it, because if you’re in a life-or-death situation and your electronic rangefinder fails … you want a backup system. But, your probability of getting a hit at long-range plumets dramatically if you don’t have a more precise range than milling targets can provide. I’ve NEVER seen anyone use this approach in the field or in competitions. The only place I’ve ever used the skill myself is in a class that was teaching me how to do it. I feel like it was a waste of time. Ultimately the range accuracy you’re able to achieve with that method just isn’t anywhere close to what you need to make a precise, long-range shot. I did a very objective analysis on this that you might find helpful:
How Much Does Accurate Ranging Matter?
Hope this helps,
Cal
Thanks Cal, I’m retired when I’m in good physical shape I shoot maybe everyday and several rifle competitions, messing with mil dot scopes is kind of a pass time , it’s a challenge to do the math in your head, I have way to much time on my hands I guess
Sounds like the life! Best of luck to you!
95.5 is the exact value; 100 is an approximation that makes the math easier to do in your head.
If you look at my comment up above, it comes from dividing the ratio of MOA-to-range (3,438) by the conversion from yards to inches (36.)
Another way to get to the same place is to say that at 100 yards, 1 MOA is (approximately) 1 inch, so for every inch you know your target to be tall, it would be 100 times that number yards away if it measures 1 MOA.
I could go into the math in a lot more detail, but that’s probably only interesting to me 🙂 And as Cal says, it’s not really that relevant in real shooting.
Ross thanks I did scroll up and read your earlier post, that does explain it, I will need to copy and paste it into my gun notes, it will take a little bit to totally sink in.
This quest to learn MOA and MILLING started about 9 years ago, I had to quit shooting pistol in USPSA due to a shake that developed in my left hand, I’m left handed, this presented a real issue for me along with a few other medical items that popped up as I hit late 50s, I new I had to shoot, but what? Rifle! I new I couldn’t steady a rifle as I did as a young man at 19 when I went into the service and shot the M14 getting the only SAEMR ribbon in my squad, I looked into Benchrest shooting I had to learn MOA to know how to adjust click value from 100 to 600 yards, as long as I can rest my left arm I’m good to go.
Then I wanted to learn about Milling for no reason other than a challenge, now I have calculators I designed in Microsoft Excel from formulas I got from Leupold and Nightforce, and I can access them from my windows phone, best part is I never have used any of it, but what the heck if I ever need to know line or gap value when you change power settings on a variable scope that ranges at 22 power but your shooting at 42 power I can easily find what my MOA OR MY MIL value has changed to. So it’s all to keep me busy, thanks Ross and Cal I appreciate your time to respond.
I absolutely disagree Ross. And the reason is mathematical error: 1 MOA does NOT equal 1 inch.
…I know you know this by reading what you wrote.
…If… 1 MOA = 1.0” @ 100 yards then it is 4.72 percent ‘off’ from reality!
1 MOA = 1 inch is not a ‘little off’, it is approaching 5% off!
This figure should be stricken from the mind of every shooter on the planet and removed from every MOA scope manufacturing plant. We all have calculators and the possibility to own match rifles.
2.54 is NOT the number of centimeters in an inch! There are exactly 2.539999999997257 cm in an inch.
There is no difference in crunching numbers; you are still calculating …either with wrong numbers or right numbers.
EXACTLY 91.43999999990125 mm equals 3.6 inches.
If you go to EXACTLY 300 yards (10,800 inches), you will find the EXACT number of triple MOA is Pi (3.141592653589793…) giving you 10.8 EXACTLY (1/1000th). It is EXACTLY triple MOA at triple 100 yards from the base.
You (and I’m not picking on you personally, but every person unskilled in mathematics due to laziness) start out fine in trying to reinstitute actual math [with 95.5, but that is wrong; it is actually 95.28] but then just fall by the wayside with all the other cloudy thinking (‘1 MOA = 1 inch roughly’). There can be no ‘roughly’ in marksmanship! Sloppy thinking is what brought us 6400 from Army artillary practices, or even the much more accurate 6283, but even that is wrong. The EXACT number is 6,283.185307179587.
A meter is NOT 39.4 or even 39.37 inches! A meter is EXACTLY 39.3700787402 inches (try finding that on the internet, you won’t …because people are mathematically lazy!).
CRITICALLY IMPORTANT – Shooting is 3 things: the physics of forces and the discipline of mathematics (especially geometry), concluding in the skill of the shooter’s concentration at the moment of trigger release on a precision instrument.
It seems few have listened to their math teacher when he said NEVER round-off inside an equation. The simplicity of this particular argument is just abide the 1/1,000th rule and keep it pure. But you know this! One will throw this out the window when one starts off with anything less than the EXACT numbers.
3.60″ @ 100 yards (1 MOA is 1.047197551196598 inches… NOT 1 inch)
75.60” @ 2100 yards (1 MOA is 21.991148575128559 inches… NOT 21 inches)
At 2101 yards, you would be out more than 1″ from reality. If you are shooting that far I’m sure you are not just trying to hit the broad side of a barn. At that distance would you really, and automatically, give up one inch of accuracy (when in all likelyhood you are going after something 18″ wide at most) simply because some knucklehead wants to say it is based on 1″ for easy figuring? You need everything you can bring to bare to ring true. At 2101 you are giving up 4.72% of the shooting discipline, and with all the other variables involved, that is a very bad thing.
Technically, scientifically, MIL and MOA are EXACTLY the same thing IF you use the proper factor of 1.047197551196598 inches, and NOT 1″. Both are based on the science of milli-radians.
The conversion is not 3.438 (you’re close!), it is 3.437746770784938. Don’t round off! Stick to the actual math! There is plenty of math to do in shooting, and each error compounds the next. If you must, because the END answer falls outside human precision of vision, or of human physical action, THEN round off. Who cares that it takes 30 more seconds to do the calculating!
Cal is dead wrong …IF… we are speaking long-range shooting (like 1k+)! We must stop generalizing and be specific! We must be exact and obey the rules to the letter (EXACT number).
Now if we could just get the scope manufacturers to make proper MOA scopes then it would not matter what 3 letters appear imprinted on them, then the only thing left would be the number of adjustment clicks on the scope.
Wow, Richard. I have to say that since we’re in the day and age of a digital rangefinder … this stuff just isn’t worth arguing about. We’re fortunate to be able to forget about all these little details, and focus on making the shot. I can honestly say I’ve never found myself doing all these detailed calculations behind the rifle.
So, I’m going to leave it at that. I appreciate your detailed explanation and the energy you put into your comment … although the approach was a bit abrasive. But going forward, I’m not going to moderate an argument on this topic. I’ll just delete any further comments. This is one of those things that people like to argue about, but it doesn’t have any relevant application for 99% of the shooters out there. It causes more confusion than it helps, and that’s not what this website is about.
Thanks,
Cal
Excellent article & comments. A great read!
Thanks, Mike!
Hi Cal,
Great article. Thanks!
I have a Bushnell Elite Tactical 3.5-21x 50mm (ET35215G) on my SSG3000. Nice scope but I don’t see how any range estimations can be done with this scope?? Kind of disappointing. I had thought the retical would have MOA markings on it but it does not. Do you have any experience with this scope?
Rob, that model seems to come with either the G2 reticle, which does have marks on it for milling targets … but they’re in milliradian (mils or mrad) not minute of angle (MOA). But, I’ve never once seen someone milling a target for range estimation, except in some kind of academic exercise. I’d recommend you go read this article I wrote on how important it is to get an accurate range to connect with long range targets. At the bottom, I talk about the hit percentages you could expect if you were an expert at range estimation based on milling the targets. Even if you’re the best of the best in the world, your odds are VERY low. We all use laser rangefinders now days. So I’d suggest you skip the exercise of range estimation, and instead invest in a good rangefinder. Unless you just enjoy figuring out how guys used to shoot, which I know some people enjoy that kind of thing … just know that virtually nobody does that anymore.
Thanks,
Cal