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Discussion Starter · #1 ·
Ok guys here we go. Go get your thinking caps on and come on back to read this.

What you need to have and know first off.
1. A calculator
2. A understanding of MOA
3. A understanding of the English unit of measure " inches, feet, yards"
4. A open mind and the ability to comprehend what you read.
5. A 100yd range
6. A computer printer
7. My e-mail address

Well here we go, A milradian is a unit of measure. To understand this unit of measure, and how it helps you is simple. All you need to do is know how big a MILRAD is at each 100yd lines you plan on ranging or shooting a target at.



To do this at home, all you need to do is take the yard line value as in the 4 from 4 00yds an times it by 3.6" and you get the value for that distance. So now we know how big a Mil is at each distance. This information will inform you the shooter to the danger space, under shot, over shot, and point blank ranges of each ZERO you use. For more info on that, come see me :)

Using the reticule for unknown distance target ranging, or hold overs/unders is the same skill set. To range a target you need to know target size in width or height or mil size for advanced MILRAD usage.

How does this work?

Very simply, to find an unknown you need two pieces of the puzzle that are known correct? So for you to find an unknown distance to a target you need the following.

Mil size + Target size = distance to target.

Very simple.

So all you do is this.

Target size x 27.778 = a number / mil reading in the reticule = Target distance. That's it.

Let's work on this. I have a 20"x40" target.



Now since I know how big a target is, all I need to do is line the target up in my reticle to get the Milrad reading.



The target to the right reads 1.2 Mil tall and .6 Mil wide. So lets use these numbers to get the range

Height:
40 inches x 27.778 = 1111.12
1111.12 / 1.2 Mil = 925.933 or 926yds ;)

Width:
20 inches x 27.778 = 555.56
555.56 / .6 Mil = 925.933 or 926yds ;)

WOW HOW DID THAT HAPPEN??????????????????????????????????? ;)

So tell me the range to the target on the left.

You should get a range of 555.56yds on both height and width.

Holds for Elevation, Windage

Now that we have covered the basic information and usage of the Mil-Dot reticle lets look at more advanced applications. We now know that a Mil-Dot reticle is a unit of angular measurement as is minute of angle. You can now use the ammunition ballistics that you have in MOA for hold-over's, hold-under's and windage to hit a target.

This is simple to do. Let's use the Federal Gold Metal Match .308 win Ammunition (FGMM) with the 175 grain bullet as an example.



Since we now have the ballistics that our rifle shoots. You need to pick a ZERO range for your scope. Then get the adjustment-ups or adjustment-downs from that MOA drop at that range to all the ranges you plan on using the Mil-Dots for hold-over's and hold-under's for.

The easiest way I have found to get the best ZERO setting on the scope is to look at your MOA from the closest range you will shoot at to the farthest. Most of us will use a 100 yard to 1000 yard ballistic sheet. For the Federal Gold Metal Match .308 win Ammunition our chart lists 37.37 MOA as the total drop. We take the 37.35 and divide it by3.43775. This gives us 10.86 Mils of total drop. Most reticules have 8 Mil-Dots with a 10 Milliradian over all size reticule. I have found that a ZERO SETTING between 600 yards and 700 yards works best for the FGMM .308win ammunition to cover 100yards to 1000 yards.

With that in mind, we will use the 675 yard data as the ZERO but you can use any MOA ZERO you would like. Some use a 400yd ZERO also to engage targets from 100 yards to 800 yards. The 675 yard data is at 18.75 MOA setting on the optic's turrets from the 100yd ZERO. Now I need to find out what my adjustment-ups and adjustment -downs are from each range to 675 yards. If you subtract 675 yard MOA from 700 to 1000 yards you get your adjustment-ups. Then subtract the MOA at 100 to 500yds from the 675yd MOA for adjustment-downs.

You're adjustment-up / down chart will look like this:



Ok the fun part. We have the entire math we could ever want now. To make a hold-over / under we must take the adjustment-up/ down and divide it by 3.438 to get is value in Mil so we can use it with our reticule. Using the same data charts this is how it's done.

I have my adjustment-downs and ups. All I have to do is take the adjustment-up or down number and divide it by 3.438 to get my mil-hold.

EXAMPLE:
400yard adjustment down from 675 yards = 11.21 MOA
11.21 / 3.438 = 3.26 Mil-Hold under 675yd ZERO
800yard adjustment up = 6.48 MOA
6.48 / 3.438 = 1.88 Mil-Hold over 675yd ZERO

To do the windage holds. All we have to do is take the true minute of angle wind drift and divide it by 3.438 and you get the wind hold in Mil.



This is how your holds will look like when you need to use them.

Elevation Holds


Windage Holds


Hope this very short explanation helps. If you need any help, ask away. Or come to a How to use a Mil-Dot reticle class. Well worth it.

John
 

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Thanks John, that all made sense to me. I need to study it a bit more, but it's very logical. :)
 

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Discussion Starter · #5 ·
jasonpeterson said:
Great post!!!! Hey John, What do you think about the Mildot Master slide rule? I received one when I ordered one of my Barrett 50 cals.
If you understand how to use it, its GREAT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

One of the best tools ever.

This is my thing, back in 2005, I shot at the ASC Sniper Match in May. We had to mil all targets only, no LRF's were allowed. 99% of the shooters used the Mil-Dot master. three people lost theirs during the match and were SOL to find ranges to the targets from that point onward.

So training point 1.

Two is One, One is None

Training point 2.

Have a backup to a backup for the backup piece of equipment.

The way I teach this Mil-Dot thing is old school, you need to know how to do the math in your head and do it RIGHT!!! Then, learn a sliding scale way of doing it, "that's the core of my class" and lastly, the easy way, with tools.

See, if you go to a match / bad guy land / hunting trip, and have the tools like a Mil-Dot Master or LRF that's great!!!! You will be much faster, if the tools grow legs and walk off you need to fall back to the basics.

Can you do that now?

John
 

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So learn how first. Then use tools to help after. Thanks for the reply.

Which shape mildots do I need to learn on. I am purchasing another scope for a Barrett model 99-1. I have a springfield 10x mildot on it now. I want a Leupold MK4 10x . On my mildot master the dots are oval. Can you give a little info on the differences? Thanks.
 

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Discussion Starter · #7 ·
jasonpeterson said:
So learn how first. Then use tools to help after. Thanks for the reply.

Which shape mildots do I need to learn on. I am purchasing another scope for a Barrett model 99-1. I have a springfield 10x mildot on it now. I want a Leupold MK4 10x . On my mildot master the dots are oval. Can you give a little info on the differences? Thanks.
Honestly,

It does not matter for the Joe Average shooter.

As far as the Mil-Dot master goes, forget the dots, look at the numbers and read the book that came with the Mil-Dot master.

But lets look at reticles only here no Rifle scope talk, just what I think in reticles.

Standard Mil-Dot = Great for movers, great for holds, takes longer to LEARN how to range a target with BUT once you learn how too, its EASY. ok at night.

Leupold TMR = Great on a 14x or higher magnified rifle scope to thin on a 10x or below, sucks at night.

IOR MP-8 = Great on 10x and higher powered optics, has alot of hold elevation, sucks at night.

IOR Modified MP-8 / A5 = I did this reticle myself for IOR. I will let others tell you what is does and does not due, not fair for my to rate my own design.

Horus "any of them" = easiest to learn on, fastest for follow up shots for under trained shooters, ranging is VERY simple, holds EASY AS PIE, SUCKS AT NIGHT!!!!!!!

USO MPR = the best for a 3.8-22 or higher magnified rifle scope. Useless in a 3.2-17 and below. SUCKS AT NIGHT Get this reticle when FOV is a non-issue like a .338 or a .50 cal.

USO GAP = best for movers, ok for holds, ranging is easy, ok at night, works in 1.8-10x and on up.

NF Mil-Dot = I like it for day time targets, ranging, holds. Forget it at night.

NF MLR, Its ok, for day time targets, to thin for me, Forget it at night.

Premier Reticles Gen II, the only beef I have is, its useless below 5x, so on a S&B 3-12x50 or a Heritage™ 3-15X50 I lose the ability to do low magnification holds when I need wide FOV. Other than that, Gen II is GREAT!!!!!!! "one point here, when I need Wide FOV for targets that are up close you can train for this and make due so?"

S&B P4, great reticle, I like it alot, not the best at all things but does alot well

S&B P4F, to thin for me, not good at night at all.

S&B P3, standard Mil-dot

S&B Klein Reticle = same thing as a PR Gen II, just a bit diffrent in the stadia sizes and small things like that. If you can find one, go get a lottery ticket, its your day bro.

Thats about it I think :)

John
 

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Great info John!

Thanks for posting. :wink:
 

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J.Boyette said:
So tell me the range to the target on the left.

You should get a range of 544.54yds on both height and width.
Nope...
If the example to the left is 2mil tall as it appears to be...
then 40" x 27.778= 1111.12 /2mil = 555.56 yards....not 544.54 yds

However if the target is 40" tall and 20" wide then the width should be 1mil...but it appears to be less than a a full mil. Perhaps .98 mil which would then calculate to approximately 544 yds. Yet the height would then have to be less than 2 mils but it does not appear to be less.

It appears the actual distance calculated would be subjective... depending on how closely a shooter estimates his target size in mils. I.E. Is it 1 mil...or .98 mil?

I realize a 10 yd variation at 55O yds is not going to be a make or break situation...but range estimation does appear to rely greatly on the tolerance used in determining target size.

Did I miss something here?

How did you determine a 544.54 yd range? That works out to a target width of .980164 mil.

Kerry
 

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Discussion Starter · #11 ·
owenslee said:
J.Boyette said:
So tell me the range to the target on the left.

You should get a range of 544.54yds on both height and width.
Nope...
If the example to the left is 2mil tall as it appears to be...
then 40" x 27.778= 1111.12 /2mil = 555.56 yards....not 544.54 yds
Kerry
I fat fingered the numbers, there. Sorry about that. I will fix it now.

Thanks for the post.

John
 

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John,

To add to your reviews of scope reticles...what are your thoughts on the old Shepard reticle? I realize the optics quality is average at best and the reticle is dated and better for hunting applications. I have been considering the Horus Hawk 3-12 x 50 but after looking at the Horus reticle it reminds me very much of a Shepard scope I have and what they were trying to accomplish 15 years ago. Similar concept but different execution.

http://www.shepherdscopes.com/oneshot.asp

I also have a Super Sniper 10X I like a lot for the money spent, but may spring for the Horus on a new AR10T I am putting together to shoot off sandbags.

My applications are strictly hunting and punching paper out to 600 yds here:







Thanks.

Outstanding thread....

Kerry
 

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Great write up... thanks for taking the time.

I wonder if we can compile the MOA average holdovers for the different rounds and barrels (14.5/16/18/20)...
 

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Thanks for the write up! You wouldnt happen to have a write up similar to that on MOA would you? :D
 

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Thanks!
 

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Simple and yet comprehensive enough. Great write up. I know several shooters on here who could use this (Cold). :lol:
 

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THellURider said:
Simple and yet comprehensive enough. Great write up. I know several shooters on here who could use this (Cold). :lol:
Heh, will see what 2009 brings :mrgreen:
 
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