I wonder if the laser RF killed or not the MilDot or other type of reticle used to aid in distance determination.

I guess out there are many experienced user who can give some insight on this.

tks!

Kill it?...Probably not.

Mil dots can be used at ranges and in conditions that laser range finders cannot...and they can also be used as aiming points for hold overs and leads.

LRF‘s are great and handy tools but they are limited to one function, they are adversely affected by bright sunlight, and they have a built in limitation on the range at which they will give a true reading on non-reflective targets.

I think not, they complement each other...

Once you know how far the animal is (LRF) you may use your Mildot reticle to actually hit it.

Although I think too much technology (scopes that calculate distance with a laser and holdover via ballistic tables and you just pull the trigger...) can in the end take the joy out of hunting with a rifle...

Antonio

Well said Antonio. In fact well said enough, that I'll just say;

What Anotnio said.

Regards--Don

The mildot system is typically used to measure distance,and hold,but this takes a bit of training.

Formula used at 10x with the leupold mil pattern is :
size of target in inches X 25.4 = Constant
Divide the constant by the size of the target in mils = equals the range to the target in Meters.
The good thing about the Mil method is you don't have to carry an extra piece of gear, and you don't have to rely on batteries.

quote:

Originally posted by RGRX in Iraq:
The mildot system is typically used to measure distance,and hold,but this takes a bit of training.

Formula used at 10x with the leupold mil pattern is :
size of target in inches X 25.4 = Constant
Divide the constant by the size of the target in mils = equals the range to the target in Meters.
The good thing about the Mil method is you don't have to carry an extra piece of gear, and you don't have to rely on batteries.

For those of us using yards instead of meters the formula is:

Height if your target in inches x 27.77 divided by target height in mils...OR

Height of target in inches divided by 36 x 1000 divided by target height in mils...OR

Height of your target in yards x 1000 divided by target height in mils.

Or...buy a Mil Dot Master slide rule and have it do the math for you real quick.

The better variable scopes having mil dot reticles use a 1st focal plane position for the reticle so the mil spacing, in relation to the target, is constant at any magnification.

I hope the MilDot will not follow the same fate as navigation skills, almost killed by the GPS

With the metric system using the MilDot is very easy, no need of complicated calculations or tables:

A "mil" is really an angle measure known as a milliradian, which is approximated for practical purposes (using equal length units) as 1,000*SizeOfTarget/DistanceToTarget = MilliRadians = Mils .

Using this formula it is easy to see that 1 Mil is equal to 10cm at 100m, or 20cm at 200m, or 30cm at 300m, or 3,5cm at 35m (or generally x/10 cm at x meters).

So if I want a holdover of 27cm at 187m I just divide 27/18.7 which very nearly equals 1.5 mils...

Naturally, if you work with yards, feet, inches and miles, things are unnecessarily complicated. (At least for those used to the metric system)

Regards, Antonio

Antonio,

With all due respect brother a mil doesn’t care what measuring system you are using it works with both equally well, and just as easily, in either meters or yards with the same amount of math involved for both. Either system seems cumbersome if you grew up learning and using the other.

By the way, how tall are you, what does your rifle weigh, what is the trigger pull...and what is the velocity of your pet load?

Not likely



John

Rick:

I never said that mils only worked with the metric system. What I said is that using the metric system with mils was easier in the sense of not having to remember cumbersome conversion factors.

As I said before, a mil is just an angular measure and can be calculated with the formula you see in my post, provided of course that you use the same length units in both numerator and denominator.

Since Americans usually use inches for the numerator and yards in the denominator, that introduces two different length scales that are related via a non-decimal factor of 30. The decimal system avoids cumbersome conversion factors and all you have to do is to shift the decimal point.

I wrote my first post mainly for Gustavo, who as an Argentinian uses the metric system and might have not been aware that in that case the formulae stated by other posters were not really necessary.

If you want to use Angstroms in the numerator and light-years in the denominator and do all the math, please do so, it is (still) a free world ;>

Incidentally: 173 cm, 4 Kg, 37cm, 820 m/s

quote:

The decimal system avoids cumbersome conversion factors and all you have to do is to shift the decimal point.

yup, if you know your target hight in mm just divide by the MILs and it will give you meters.

The formula given above where:
in. x 25.4/MILS = meters
does just that.

Or do like I do and look it up on the MILDot master. much easier

Not to mention that in a combat environment where both sides posses the technologies, the laser identifies the probable location of the shooter as well as the yardage to the shootee...

quote:

Originally posted by tiggertate:
Not to mention that in a combat environment where both sides posses the technologies, the laser identifies the probable location of the shooter as well as the yardage to the shootee...

The military laser range finders have to be plugged into another unit in order to give the GPS location of the target. They are heavy and cumbersome to use.

Once you are used to the mil theory and take the time to practice with it the math becomes second nature...whether you are using meters or yards doesn’t really make allot of difference, use the one that pleases you and the one you are most comfortable with.

Most of us in the USA over the age of 30 are much more comfortable using inches, feet, yards and miles to measure size and distance.

Accurate estimation of the size of your target (in whatever format) is the key to using a mil-dot reticle. I have both a spotting scope and a set of Binoculars with mil-dot/mil-scale reticles and I can practice sizing and ranging things with them just about anywhere without alarming anyone like I would if I used my rifle/scope.

Rick:

I agree 100% with you. I also have binoculars(EDF 7x40) with a mil-scale on them, and it is a fun thing to range things with it. It is of course not as precise a method as a LRF. I also use the mildot to approximately compensate for the trajectory of my bullet when shooting at longer distances...

Antonio

quote:

Originally posted by Antonio:
...
Although I think too much technology (scopes that calculate distance with a laser and holdover via ballistic tables and you just pull the trigger...) can in the end take the joy out of hunting with a rifle...

Antonio

Yeah, these new fangled breach loading cartridge rifles take all the fun out of hunting with a rifle. Dang new technology. Time was when a flintlock and a sharp eye were all that a man needed in life... ;^)

quote:

Originally posted by tiggertate:
Not to mention that in a combat environment where both sides posses the technologies, the laser identifies the probable location of the shooter as well as the yardage to the shootee...

Kinda like the old observation that tracers work both ways

AllanD

So how far is this guy?

[img] http://img361.imageshack.us/img361/9739/moa4po.jpg [/img]

My calculations lead me to believe the target is 714m distant.

I’m gonna say 625 to 650 yards...or 571 to 594 meters.

I guessed his height in the chair at 48 inches...or 121 centimeters, and he appears to be approximately 2.1 to 2.2 mils in height.

I'll say 660 to 680 meters.

His butt to his shoulders is one MIL (assuming 26" for measurement. This gives 660M
As a secondary, the 8" concrete block next to him takes up .3 MILs so this come out to 677 meters. Two readings yeilding results w/in 3%.

So how far is he?
Three MIL dot users with 3 different answers and all them different enough to cause a miss.

Rick and Sargent, did you guys use a secondary target to varify range? I find that helps me if I can get two different readings on a target or target area for comparison.

Rusty,

I estimated his height sitting in the chair, butt to shoulder, butt to knee, knee to foot, head size, height of the chair back, and height of the wall behind him. I guess my estimates on these measurements are just a bit smaller that yours.

So here appears that at least for some people, the MilDot is good enough to have assured a long life despite the fact LRF are being reduced in size and features, and cost every day. To be honest, it's good to hear that!

Hope that we as hunters never loose this skill.

quote:

Originally posted by Gustavo:
So here appears that at least for some people, the MilDot is good enough to have assured a long life despite the fact LRF are being reduced in size and features, and cost every day. To be honest, it's good to hear that!

Hope that we as hunters never loose this skill.

LRF’s are great tools...but like all tools (including mil-dots) they have their pluses, minuses and limitations.

As you have just seen from the previous posts mil-dots are totally dependent upon the accuracy of the target size estimates made by the operator. Three of us all made similar but different estimates as to the size of the target and therefore the distance.

Rick, I rejected many of the "check dims" you used because I wasn't comfortable with start and stop locations. Like foot to knee, it looks like he has one foot on the other and the ankle turned over, like I sit in my chair every day. Or maybe his feet are on a platform... at anyrate I din't like the quality of the mesurement. Same reason I didn't like the hight of the chair, I couldn't tell what his feet are resting on.
I didn't like the forearm to hand as the elbows are on the chair arms and his hands are in his lap. The forearm would measure shorter than it really is.

I took some more time with this and using the wall and some Assumpions for the wall behind him, 6" blocks 8 courses, .5" of mortor between rows makes for 3.5+48 or 51.5 in. round it to 52" over 2.2 MILs puts the target ar 600m even.

Piss on it; take the average, go with 630 and call in a fast mover with napalm.
Would that be cheating

Rusty,

Looks like we were both looking for lots of things to estimate the size of...and that’s what counts. Take an average of a few different things and say a little prayer.

I assumed your 6 inch cinder blocks were 8 inchers so there you go!

Either way I don’t buy the 700+ meters as was originally guessed...but hey, I’ve been way off before and probably will be again.

there are two different size blocks, the wall behind is made of smaller blocs than thr repaired area of the wall to the left. the repaire blocks look like modern 8" blocks, there are some on their side, the old section of the wall is made from a smaller block.
Beats me what size Iraqi cement blocs are but I had to guess at something, like you said, average out a couple of readings, say a prayer ans squeeze gently.

We were both pretty close is our “guessesâ€. You said an even 600 meters (656 yards) and I said between 625 and 650 yards.

I would guess at first sight that the target´s size is 120-130 cm. As it measures 2 mils, a mil at that distance is 60 to 65 cms, which gives a distance of 600 to 650 meters.

Antonio

quote:

Originally posted by Antonio:
I would guess at first sight that the target´s size is 120-130 cm. As it measures 2 mils, a mil at that distance is 60 to 65 cms, which gives a distance of 600 to 650 meters.

Antonio

He measures a bit over 2 mils to my eyes, but all of us are guessing so your guess is probably as good as mine.

My guess is over the 2 mils i.e. to his neck to make the calculation easy.

Antonio is exactly right on the "angular" concept. So much so that turns out the mil-ranging formula is not milliradin-specific at all, and can be used with any multi-stadia reticle out there-- plex, custom, any 2 points at 1 location relative to any other 2 points at a different location.

quote:

Originally posted by sscoyote:
Antonio is exactly right on the "angular" concept. So much so that turns out the mil-ranging formula is not milliradin-specific at all, and can be used with any multi-stadia reticle out there-- plex, custom, any 2 points at 1 location relative to any other 2 points at a different location.

You can arbitrarily assign a size “value†to anything in relation to something else...but to use mil formulas the reference point[s] on your reticle must be spaced/sized in mils.

Rick, the most basic formula is:

tgt size x reticle subtension distance/reticle subtension/quantity of bracketing gap tgt. subtends = range

It's the geometric angle formula that defines the relationship between a measurement at one distance relative to another measurement at another distance. It doesn't make any difference whether the measurement is a milliradian or not. It can be any measurement. You could actually use the "modified mil-ranging formula" to range the moon between two points of a window sill if u want--- or archery sight pins.

Here's how "reverse milling" would work to determine the size of the pr. dog Leupold uses in their VH reticle.

1)tgt. size = P
2)reticle subtension distance = 100 yds.
3)reticle subtension (instead of a milliradian)= 2.45"
4) quantity of bracketing gap target subtends = 1.0
5) range = 300 yds.

Plugging in all the variables gives--

P x 100 / 2.45 / 1.0 = 300

P= 7.4"

In fact something i think's kinda interesting is to leave the reticle subtension itself an unknown to calculate a more accurate "relative subtension" by measuring the reticle subtension at the distance u intend to use the ranging system at. This may be a more accurate way of ranging with say a plex reticle or a ballistic reticle, since you're establishing your ranging std. at longer range. Just set various size tgts. of known dimension at lasered ranges, range them, apply the "MMRF" again to effectively reverse mil again to calculate the avg. relative subtension.

Don't really know about this would be fun to try as a research project tho.

The formula utilized in mil-dot reticles breaks a circle (360 degrees) into 6,283 parts...or 17.5 mils in one degree...or one mil equals 0.573 degrees...or one mil equals 3.438 MOA.

This is a constant no matter what the range, no matter what the size of the target, and if the scope is a fixed power or has a first focal plane reticle, no matter what the magnification...one mil (the distance from center to center of the dots) will ALWAYS subtend 3.438 MOA.

Using window sills and archery pins is totally dependant upon placing your eye a specific distance from either...silly analogy!

Silly ehhh?? Actually, i think it's rather insightful if i don't mind saying so. Others do too. In fact, i'll be making some $ on that very concept end of this year.

Rick, not to nit pick (becuase mathimatically you are absolutley correct) but the Army rounded that 6283 value up to 6400. That's why the Army compass has MIL marks that go from 0 to 64(00). It was origanally done for artilery and becuase the sniper program was being reestablished after WWII as dual role shooter/observer the MIL dots in the scope are calibrated to match so that a sniper can call targets and corrections accuratly for artillary.
So acctually Army MIL dots subtend 3.375 MOA Center-To-Center.

I have read this in several sources, particularily of the Viet Nam time period, and from current info on MIL dot use.
(I am not a sniper nor do I play one on TV)

EDITED:
Here is one of my sources. MIL DOTS

edited again:
Rick as you can see in the above link USMC MIL dots use the true mathimatical MIL for definition. I use Army dots (cus that's what I bought with out knowing any differance) so I tend to forget the USMC dots are slightly different from what I use.
I appear to be suffering from Tunnel Vison.

Rusty,

As far as I know the Unertl 10x USMC sniper scope was the first rifle scope to have a mil dot reticle. The patent date on that scope is 1975 I believe. The Military binoculars have had mil scales in them since the 1930’s.

Before his death I had the great opportunity to have a whole bunch of long talks with Dick Thomas at Premier Reticle about scopes in general and mil-dots in particular. He used to build the mil dot reticles for Unertl and Leupold...as well as for many other brands out there.

One of the books on Sniping written by an arm chair warrior shows Army mil dots, but USMC math!

The MIL dots must have been in spotting scopes or binos then rather than rifle scopes. I don't doubt you on the Unertl date.

I am quite sure I read teht bit about training snipers to use MIL dots so they could be forward observers for artillary. I makes sence that the sniper/observer would use the same (if incorrect) MIL as the artillary. If a call was off by .5MIL at 20 miles, it could really foul up ones day.

It is interesting that the USMC went with true MILs as opposed to the established Army MILs. Do you know why? Or do you think is was simply one armed services branch not communicating with the other? (Like that would ever happen )

Rusty

The difference between the Army reticles and the USMC reticles is in the size (value) of the dots, not the spacing of the dots or the assigned value of a “mil.†They both divide a circle into the mathematically correct 6,283 parts rather than the Artillery standard 6,400 parts.

The reticles in the older military binoculars for adjusting indirect fire weapons used the Artillery 6,400 figure for the spacing of their lines. I’m not exactly sure what figure is used in the newer military binoculars using mil scale reticles.

The Military was using binoculars with mil-scales (lines rather than dots) way before they started using mil dot reticles in sniper scopes.

Again, I believe I am correct when I say that John Unertl was the first manufacturer to put a mil dot reticle in a rifle scope...and he did that when designing the USMC 10x scope for the M40A1 in the late 1970’s. That was also the first rifle scope designed specifically from the ground up as a sniper scope for a particular rifle, caliber and load.

The new S&B scopes being adopted by the Corps have Premier GenII mil dot reticles (invented by Dick Thomas) installed. Those reticles, through the size of the dots and small hash marks, allow the user to quickly break the reticle down into 1/10th mil increments which allows a skilled user to be very precise in estimating range, leads and hold overs.