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Discussion Starter #1
Hi! I’m a translator from Germany, currently working on an action/thriller novel by an American author. There’s a passage in which he describes a shooter taking aim at a long range target using a mildot reticle. Either that passage is written too weirdly or I’m just too stupid to figure it out, so I thought I might ask a couple of experienced shooters for help. Personally, I don’t know any, which brought me to this forum. One more thing: I am not a shooter myself, and in general I don’t have much of an idea how firearms, scopes and reticles work. So, if any of you would be so generous to try and explain this passage to a layman so I can translate it well and make it accessible to german readers, that would be awesome and I would be grateful for your help.
Here it comes:

"He pivoted slightly, found a bush coned in snow, which he took to be of three feet girth. By covering it in the scope with mil-dots and racking through the math - the black mass covered two dots; multiply the assumed one meter in heigth by one thousand and divide by two to get the approximation of a thousand yards: say, less than a thousand but more than nine hundred yards he held four dots high."
 

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The Shadow (Moderator)
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There are a lot of problems with that passage, but here is some info for you.

Mil in Mil-Dot comes from a unit of measurement, called the miliradian. If he is a military type, using yards, feet, and meters together is incorrect, but that is another issue. Also, if he is using a true mil-dot FFP(first focal plane) scope, I can't fathom why he "held" over the target. The whole point would be to dial the correction, unless in a hurry; which is doesn't sound like is the case.

IF the target is covering 2 mil dots, that is a distance of only 1 mil(dot to dot). Assuming he is at my atmosphere(900 ft 30% RH, 90 deg) and assuming he is running military M118LR type ammo from the spec'd velocity out of his 7.62 Nato, AND assuming he is zeroed at 100 yards;
That distance is 1,093 YARDS away. The correction for that distance is NOT 4 mil. 4 mils are the correction for JUST over 500 yards.
For the actual distance, the correction is 13.3 mils.

So what is he shooting? The above is the correction based upon the 7.62 Nato sniper ammo. another cartridge will significantly change that, but the distance is incorrect regardless of cartridge used. It is far beyond the 950 mark.
 
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For the land of fiction, readers need only know or understand that the riflescope has marks (dots) that can allow shooters who know the rifle & scope combination well enough to make a shot at very long ranges. Those that might understand what "mil dot" equipped scopes can do will understand. Those who do not know how they can help a shooter on a very long range shot need only understand that the scope and shooter's knowledge of his weapon allowed him to make such a shot successful.

I hope that makes sense as to what you are trying to portray in German.
 
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You might want to consider that most fiction writers know little if anything about long range shooting. They merely throw around 'jargon'; often poorly used.

I'd just do a literal translation but use consistently "Meters", and drop out the 'yards'.
 

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Discussion Starter #5
Thanks for your feedback! So, would you agree that this passage is somewhat confusing and unclear? This guy makes a point of knowing his stuff and is a hobby shooter himself, but it often seems to me that the more he tries, the more he messes everything up. Mostly I thought it was due to my understanding of english (or HIS english in particular), but he does seem to mix things up badly sometimes. Anyway, I think I’ll try to find a "workaround" for this passage that conveys the gist of it without including all the details, as Tnhunter suggested... Suggestions still welcome, though.
 

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The Shadow (Moderator)
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Thanks for your feedback! So, would you agree that this passage is somewhat confusing and unclear? This guy makes a point of knowing his stuff and is a hobby shooter himself, but it often seems to me that the more he tries, the more he messes everything up.
Correct.
People don't interchange feet, meters, and yards when trying to do calculations in their heads.

As TnHunter suggested, the fact that he doesn't know distance isn't surprising. For this subject matter in a book, the author has to say he is a shooting enthusiast. He is selling a product, if you went to buy a car and salesman told you he doesn't know what a car is; you probably won't talk to him. But you may not stop talking to him if he simply doesn't know as much as you do.
 
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"He pivoted slightly, found a bush coned in snow, which he took to be of three feet girth. By covering it in the scope with mil-dots and racking through the math - the black mass covered two dots; multiply the assumed one meter in heigth by one thousand and divide by two to get the approximation of a thousand yards: say, less than a thousand but more than nine hundred yards he held four dots high."
There are a couple issues, separate from the shooting related issues:

1. The most glaring issue is the math error.

One meter (in width or height) x 1000 / 2 = 500 not 1000. If he can't divide 1000/2 to get 500, he's got serious problems with doing math in his head.

2. He references target girth of 3 feet and then uses target height of 1 meter. I don't know anyone who can tell the difference between a 3 feet (1 yard) wide target and 1 meter wide target at 1000 yards or 1000 meters.

I also don't have any real issue with a shooter who grew up with the imperial system estimating target size in feet or inches and then converting that to cm or m for range calculation purposes.

But the shooter should be using a consistent target dimension (height or width) when ranging, and

The shooter should be working in consistent units.

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There are some shooting issues as well:

A. Range estimation with a mil dot using meters.

The formula for range estimation with a mil dot reticle in meters is:

Target Height in meters / Height in mils x 1000 = Range to target in meters.

(Obviously you can also measure target width and the mil subtension in width as well.)

Either way, if a 1m target subtends 2 mils, then the range is 500 yards.

1m / 2 mils x 1000 = 500

With the order of operations rules in math you can multiply or divide in any order for this calculation, so it can also be solved as:

1x1000 / 2 = 500;

which is easier in your head and probably would have avoided the mistake he made.


B. Range estimation with a Mil dot using imperial units - yards

Lots of self taught long range shooters, in particular civilian shooters, will use yards with a mil dot reticle. It's workable but it's less elegant.

The easiest way to do it is to work in yards.

Target height in yards / height in mils x 1000 = range to target in yards.

If a target is 24" wide, you'd use .75 yards, then divide by the mils and multiple by 1000 to get the range - or some combination of that:

.67 x 1000 = 670 (which is super east in your head as all you're doing is moving the decimal) and then divide 750 by the mills. If the target is subtending .5 mils in the reticle, then it's 670/.5 = 1340 yards. (which is easier to do in your head by multiplying 670 by 2 rather than dividing 670 by .5, as mathematical it's the same thing, just a lot easier).

C. Range estimation with a Mil dot using inches, and with mixed units

Unfortunately, I encounter shooters who use inches for estimation of target size, and the formula for inches is more difficult to do in your head:

Target size in inches x 27.77 / Height in mils = range to target in yards.

So for a 24" target, you have to multiply 24 x 27.77 and then divide it by the height in mils.

24x27.77 = 666, and then 666 / .5 = 1332 yards.

I can't crunch those numbers in my head, so a calculator becomes a go/no go item if you're using that approach.

Almost as and are the shooters who want to use target size in inches and then use range to the target in meters.

In this case the formula is:

Target size in inches x 25.4 / Height in mils = range to target in meters.

The math is just as hard:

24x25.4 = 609.6, and then 609.6 / .5 = 1219 meters (which is 1333 yards).

In summary, all of the above get you to the same range, but it's a lot easier to generate that range in your head ,or on a calculator, if you stay with yards and yards, or meters and meters and not get sucked into estimating target size in inches.

D. Significant figures and limiting variables

Some folks will no doubt show up and flame me for the error in the yards calculation, but that's a 7 to 8 yard difference over a 1300 plus yard range, and thats well within the other errors in the system.

For example you are estimating the target width or height in mils and there's always a range of error there, both in terms of estimating exactly how many mils the target subtends, and then estimating exactly how tall or wide the target happens to be.

Short guys will mil farther away than tall guys even when both are standing identical distances away from you. So at best you are estimating a standing target you assume is average height, and unless the target aligns exactly with the dots in the reticle, you're estimating how many tenths of a mil the target is actually subtending. Both estimates introduce potentially significant errors.

Way too many people get hung up on "precision" while failing to realize that the precision they can achieve is constrained by the most inaccurate variable in the calculation.

In that regard, I'm ok with the shooter in your text ball parking the range estimate, based on the ball park estimate of the size of the bush. There is no sense measuring with a micrometer, when you are going to mark the line with chalk and then cut the board with an axe.

E. Mil dot differences.

There are also differences in mil dots that can effect the accuracy in miling the target

For example the reticle in a US Army issue scope will use round dots that are .2 mil wide (.1 mil each side of center). They are spaced 1 mil apart, which means there is only .8 mil between them and 1.2 mil from outside edge to outside edge and 1 mil from inside edge to outside edge.

The USMC on the other hand uses football shaped mil dots that are also 1 mil apart center to center and inside to outside edge, but they are .25 Mil wide and .75 mil apart.

In addition, there are mils and there are artillery mils. A mil is an angel measure that is technically 1/6283rd of the circumference of a circle. However the artillery types rounded that to 1/6400 of a circle, as it was accurate enough for artillery purposes.

Some scopes use 1/6400 as a mil, while other use the more exact 1/6283 for a mil.

I wouldn't get too hung up on the it if the scope is using 1/6400, as it's not the least accurate number in the calculation.

F. There are also MOA reticles

About 90% of current military trained shooters use Mil, in large part because most military forces work in meters, it also keeps things neat and tidy, and mil corrections are a little easier to record and communicate as "5.2 mils" is more compact to write or say than the equivalent "17.75 MOA", which has twice the digits.

However if the shooter in the story is old school, not current/recent military or is civilian he or she might prefer mils.

There are advantages to the system for a shooter more comfortable with imperial units.

1 mil = 3.438 MOA, so 1/4 MOA adjustments are slightly more precise than .1 Mil adjustments.

For those folks who are better at estimating target size in inches, the math is super easy:

Target size in inches / Target size in MOA x 100 = range to the target in yards.

In the example above a 24" wide target that subtends 1.8 MOA would be 1333 yards away:

24/18 = 1.33, 1.33 x 100 = 1333.

The advantage of the smaller MOA unit is that there is less extrapolation between hash marks in the reticle than their is between mil dots, so the estimate is potentially more precise.

The same complications occur when you start mixing units or when you start mixing MOA and mils.

Both Mil and MOA work, so just pick an angular measure, pick your units of distance, keep them compatible to simplify the math, and then stay with them.

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As for the ballistics, if the shooter is holding 4 mils high at a ball park 950 yards range, then he'd have to either a) have about 6 mils in elevation already put on the scope or b) have a basic zero of about 700 yards to expect to hit a target 950 yards away with a 4 mil hold.

But that's assuming the use of a .308 with M18LR ammo. Without knowing the cartridge and rifle being used it's hard to comment in much more depth.

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In any case, from a technical perspective, it makes sense to match the reticle, the units and his style of shooting to the shooters back ground and training, as well as with the era in which the story occurs.

For example, in the immediate post Vietnam era when scopes were still simple, adjustable turrets less reliable, and snipers could still do math in their heads, it was not uncommon to have a 500 meter basic zero on a .308 using a fixed 10x scope with a mil dot reticle. The shooter then used the reticle to apply the additional windage and elevation holds for shots at longer range. And in the M118 (173 gr FMJBT bullet) days, the engagement ranges with a .308 are normally 500 to 800 meters. Shooting from less than 500 meters often meant the sniper took unnecessary risks of exposure, and shooting from much farther than 800 meters meant the probability of a first round kill fell to unacceptable levels.

Modern laser range finders that provide a much more precise estimate of range are what have made the PKs on long shots more acceptable past 800 meters with cartridges like the .308.
 

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Discussion Starter #8
Thanks for all the info! I can’t say I was able to follow it all, but that’s ok. Your first point, the simple math error, was something that occurred even to me... It’s astonishing what kind of errors end up in a printed book. For the rest, there are a couple more informations about the shooter, his gear, his elevation etc., but I would have to find and quote them, and I don’t know how much it matters to you... So far, I see what the main problems are. I just converted the passage into something less detailed (and less flawed).
 

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You could say he used his mill dots to judge the distance of the target so he new how much to allow for the drop of the bullet due to gravity afecting the bullets path through the air.
That is similar to reality,:)

you learn some thing new every day ,I had no idea people were going around judging distance by doing that.I am surprised that it is possible to do.I thought it would matter to much being out a bit when you judge the bush.so to speak.
 

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/...I had no idea people were going around judging distance by doing that.I am surprised that it is possible to do.I thought it would matter to much being out a bit when you judge the bush.so to speak.
It is a bit of a problem and I don't think all that many people go around ranging that way anymore with the widespread availability of decent laser range finders capable of ranging more accurately at that range under most (but not all) conditions.

Let's say it's a cold day with a temp of 25 degrees F and a barometric pressure of 30" of Hg and a resulting density altitude of -2500 ft. With M118LR and an estimated range of 1000 yards, I need 44 3/4MOA of elevation up from a 100 yard zero.

However if the target is actually only 950 yards away, I'd only need 40 1/2 MOA and I'd have 4 1/4 MOA too much elevation (whether I am holding over or putting it on the scope). At 950 yards, that extra 4 1/4 MOA of elevation amounts to 42.27" - in other words I'd be shooting 42" high. If I'm shooting at a person, even if I hold on his mid line, I'm going to shoot over his head with a 50 yard range estimation error at that distance.

If the range is actually 970 yards (only a 30 yard error), then I'd need 42 MOA and I'd only have an extra 2 3/4 MOA of elevation - placing me 28" high. In this case holding on the mid line of the target would put a round squarely in his head - assuming the windage is correct, and the rifle, cartridge and shooter are at least 1/2 MOA accurate.

Obviously, a 20-30 yard range estimation error at that distance with a .308 is significant All things considered though, if I have to be wrong I want to be wrong slightly on the long side in terms of elevation applied on the scope, hold low and then hit him high, but I still need to be accurate within about 20 yards in my range estimation at 900-1000 yards, and that's about 97% accuracy.

When you consider that the target might be average a 69" in height, or tall at 72" in height, that's a 5% error already, even before I factor in the errors in bracketing the target in a mil dot or MOA reticle.

In general, in the era before laser range finders, the practical effective range for a .308 with M118 special ball was around 800 yards as beyond that the combination of trajectory and mil dot ranging errors become too large to ensure a high probability of a hit.

And as a practical matter, I doubt the shooter would range on a bush of unknown size, if he has a person sized target to use. Even a 5% error is much better than a totally unknown sized bush.
 

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That is impresive being able to get that amount of distance judjment accuracy ,what a skill to have.
 

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That is impresive being able to get that amount of distance judjment accuracy ,what a skill to have.
It's either poorly done sarcasm, or you're still missing the point that even with a mil dot reticle that much accuracy is impossible to achieve with consistency at 1000 yards.
 

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No sarcasm sorry to give you that impression.
You are saying that it is to inconsistant because there is veriabels that make it hard to judge under 50 mtrs ,I am surprised that it is possible to judge within 100 mtrs.
When I see a friend today I am going to tell him I was wrong about mill dots on scopes.
What is possible with maths bewilders me.
I thaught there would be two hopes of judging between say 800 to 1100 ,two hopes being bucklies and none.
The fact that some one who is good enough ,with the right size estimation can get down to under 50 mtrs is awsom ,wether they do it consistantly or not.:)
 

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The Shadow (Moderator)
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It is a bit of a problem and I don't think all that many people go around ranging that way anymore with the widespread availability of decent laser range finders
I still do, and enjoy honing the skill. It's about like anything anymore, buy equipment, or learn the skill. Perhaps it just the folks out here, but it is stunning how many I run into who have their range finders die while shooting. Once that goes down they have ZERO range estimation ability. Personally think that why everyone shot their deer "at almost 500 yards".
 

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Any chance of you posting a excample of a long rang target aquasition in step form.

From an hopefull shreck.
 

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I still do, and enjoy honing the skill. It's about like anything anymore, buy equipment, or learn the skill. Perhaps it just the folks out here, but it is stunning how many I run into who have their range finders die while shooting. Once that goes down they have ZERO range estimation ability. Personally think that why everyone shot their deer "at almost 500 yards".
I hear you there. Show the average hunter a 200 yard distance and he'll tell you it's 300 yards. Show him a 300 yard distance and he'll tell you it's 450 to 500 yards. A 150% overestimate of range seems to be the norm.

To be fair though, way too many "long range" shooters mistake a few basic shooting skills with long range precision shooting and while they may shoot some reasonable groups at long range - it's often at known distances, with several sighters, off a bench and in fairly calm or steady wind conditions. They lack many of the skills that are essential for practical long range shooting in the field.

Given similar target size and cartridge:

I'm much more impressed with someone who can make a first shot hit at 750 yards with a .308 than I am with someone who takes a half dozen rounds to start making hits at 1200 yards with the same .308;

I'm much more impressed with someone who can make first round hits on targets at unknown distances from 500 to 750 yards than I am with someone who can make first round hits at a known distance of 1000 yards;

I'm much more impressed with a shooter who can make consistent hits in windy conditions than I am with someone who only shoots in calm air; and

I'm much more impressed with someone who can make consistent hits off a bipod or in a supported prone position that I am with someone shooting off a bench rest under otherwise similar conditions.

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I also agree on the over reliance on electronics.

I've had some interesting arguments in other forums where shooters who are mixing units (and in the process are making the math for ranging exceptionally hard) insist that it it's not a problem/ They are in effect stating that they never even consider using a mil dot or MOA reticle for ranging the target, failing to learn that skill or use that capability even as a back up.

Personally I like ballistic apps, particularly when looking at different cartridge and load possibilities. But when it comes to actual shooting, I prefer a whiz wheel as it is fast, accurate, impervious to moisture, weather or being dropped, and it is not reliant on batteries.
 

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Discussion Starter #17
Got another problem here... The context is as follows: One guy has been chasing the other guy through the snow and they’ve taken some shots at each other. Now guy one has entered a house through a cellar door, and guy two has seen him go in. He wants to take him out (through the closed door, actually... pretty dumb).
So here’s another passage I simply can’t make much sense of (the second sentence in particular):

"He dropped to one knee, braced the rifle on his leg, found the good shooting position. IT WAS FIVE HUNDRED YARDS IF IT WAS AN INCH, BUT THAT HAD TO BE THE ZERO ON THE RIFLE, FOR THE OTHER MAN HAD COME SO CLOSE TO HIM SO OFTEN."

What is the "it" he’s talking about? What is "the zero on the rifle"? What does that have to do with the fact that he came close to the other guy?
 

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It is the distance from him to the target.
Zero on a rifle is were you set the cross hairs that are used for aiming to conect with the falling arc of the bullet.
Potentialy the guy no 1 is rationalising the distance the rifle is zero'd at by near misses made from guy no 2 to gage his shot .
I presume guy no2 is the owner if the rifle os else it does not make any sense .
 

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The Hog Whisperer (Administrator)
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Poor assumption as to how another rifle is zeroed, or that it is zeroed at a known range, or stayed zero after being dropped, captured, etc. Snipers, in particular, used to be trained to leave the gun zeroed at a particular range and just hold off when shooting at other ranges.

But up to the author ;)
 
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Discussion Starter #20
It is the distance from him to the target.
Zero on a rifle is were you set the cross hairs that are used for aiming to conect with the falling arc of the bullet.
Potentialy the guy no 1 is rationalising the distance the rifle is zero'd at by near misses made from guy no 2 to gage his shot .
I presume guy no2 is the owner if the rifle os else it does not make any sense .
Well, if 500 yards is the distance, what about that inch he’s talking about?
Guy no.2 is not the owner of that rifle, he’s got his own one. :)
I understand in general what the zero is, but this sentence still doesn’t make any sense to me.
 
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