Advanced Marksmanship Minute of Angle

[urbancamo]

MOA= (Inches * 100)/ (1.047 * yardage)

How accurate is this formula considering the value of each click changes the further out your shooting?

I'm having Luepold build custom M1 dials and i'm trying to figure all this out before my scope gets back. I have a pretty good understanding now but there is still some confustion. I am more concerned about the windage at this time however. How should I go about calculating MOA for wind speeds ranging from 5 - 20mph? I know each click on the windage turret will be true 1/4 MOA, so whatever MOA I get needs to be multiplied by 4, or divided by .25? Any input on this subject would be greatly apprecieated. I'm having trouble sleeping at night with all this running through my head!

 

[deadly0311]

Re: Minute of Angle

have no fear Lindy will be here in a second to make this seem so simple.

 

[urbancamo]

Re: Minute of Angle

I kinda figured he would show up. I'm hoping he makes it real simple. I want to learn as much as I can about this but I have to start with the basics first. I didnt even realize the spelling errors that I made when i started this thread....I'm really not that dumb...I dont think?

 

[Jaeger308]

Re: Minute of Angle

When thinking MOA understand it is a length or distance at a particular range not an angle.

True MOA=1.047” @ 100 yards, 5.23” @ 500 yards etc……..


When you put adjustments on your turrets get the term “Clicks” out of your head for overall adjustments. Your turret should have MOA increments etched so if your firing solution for windage is 3.0 MOA dial 3, not 12 clicks even though they are the same. For a 3.5 you would only think clicks for the .5 part; adjustment would be dialing 3 then plus or “push” two clicks to achieve the .5 on a .25 turret.

 

[urbancamo]

Re: Minute of Angle

Ok that makes sense. So with that being said what is the best way to accurately calculate MOA? I have two different tables right now. One is from a marine sniper handbook and the other is from the hornady ballistics calculator? I dont have any other ballistics software so would anyone have an easier way to get accurate figures?

 

[Jaeger308]

Re: Minute of Angle

Every weapons system is different, published data as you have is a guide to get you close. Real world data will need to be confirmed by you. Add changes in Bar. pressure, tempature and even your data will change. Establish base line data in your home enviorment and go from there. Reading and understanding wind is half science half art form, climb on the learning curve and enjoy the ride.

Use the search feature here on the hide there is plenty of information to study ballistics and ballistic programs but more important go shoot ALOT!

 

[Jaeger308]

Re: Minute of Angle

Field firing Solutions Link

Go here and download the pdf manual it will help to get you going and better understand external ballistics.

 

[Lindy]

Re: Minute of Angle

An MOA <span style="font-weight: bold">IS</span> an angle.

To be precise, it's one-sixtieth of a degree.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I dont have any other ballistics software so would anyone have an easier way to get accurate figures?</div></div>

Here is the gold standard for ballistic programs:

JBM Ballistics

If you have questions about setting it up, notice that the label on every field has a little question mark link. Click on that to understand how to enter the data for that field.

 

[r44astro]

Re: Minute of Angle

duh

 

[Sterling Shooter]

Re: Minute of Angle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: urbancamo</div><div class="ubbcode-body">MOA= (Inches * 100)/ (1.047 * yardage)

How accurate is this formula considering the value of each click changes the further out your shooting?

I'm having Luepold build custom M1 dials and i'm trying to figure all this out before my scope gets back. I have a pretty good understanding now but there is still some confustion. I am more concerned about the windage at this time however. How should I go about calculating MOA for wind speeds ranging from 5 - 20mph? I know each click on the windage turret will be true 1/4 MOA, so whatever MOA I get needs to be multiplied by 4, or divided by .25? Any input on this subject would be greatly apprecieated. I'm having trouble sleeping at night with all this running through my head!</div></div>

Let's see if you figured it out. The firing line is 600 yards to target and line of sight is horizontal. There's a full value left to right cross wind raising dust and blowing loose paper at mid-range. Using your wind formula with a correct constant of 10 how many quarter minute clicks of windage will you need to take to get a good hit? If you favor rather than taking clicks how many inches will you hold off. Try to answer without using a ballistics chart. All you need to answer is an understand of wind velocity, zeroing/MOA, and wind formula concepts. Knowing this stuff is essential to good shooting. Answering this question will take maybe 4 seconds of math you can do in your head.

 

[Jaeger308]

Re: Minute of Angle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lindy</div><div class="ubbcode-body">An MOA <span style="font-weight: bold">IS</span> an angle.

To be precise, it's one-sixtieth of a degree.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">I dont have any other ballistics software so would anyone have an easier way to get accurate figures?</div></div>

Here is the gold standard for ballistic programs:

JBM Ballistics

If you have questions about setting it up, notice that the label on every field has a little question mark link. Click on that to understand how to enter the data for that field.
</div></div>


Lost in my typing translation, yes MOA is an angle, but IMO it is better to teach people to consider the term as a length or distance at range. The fact that when we use MOA or multiples of it, it is a constant. Now we could discuss, that, scopes do not all travel true MOA and should be measured/calibrated and any error of this constant be prorated into turret solutions.

 

[Greg Langelius *]

Re: Minute of Angle

Tossing the .047" completely out of your figuring puts one off by under 1/2" at 1000yd. If anyone here can distinguish and hit two objects 1/2" apart at 1000yd, my hat's off to ya.

KISS = "Let's keep things in reasonable proportion, folks...".

Greg

 

[urbancamo]

Re: Minute of Angle



Let's see if you figured it out. The firing line is 600 yards to target and line of sight is horizontal. There's a full value left to right cross wind raising dust and blowing loose paper at mid-range. Using your wind formula with a correct constant of 10 how many quarter minute clicks of windage will you need to take to get a good hit? If you favor rather than taking clicks how many inches will you hold off. Try to answer without using a ballistics chart. All you need to answer is an understand of wind velocity, zeroing/MOA, and wind formula concepts. Knowing this stuff is essential to good shooting. Answering this question will take maybe 4 seconds of math you can do in your head. [/quote]

I have a feeling i'm gonna get torn apart after posting this, but this is what I have learned about my rifles ballistics. Keep in mind that I have not tested any of the formulas yet as I have not received my scope back from Luepold yet.

My rifle at about 600 yards with, according to your description, a 20mph full value cross wind will be roughly 19.5 MOA or 78.15 clicks. Sterling Shooter will you please explain how you would go about that calculation?

 

[Jaeger308]

Re: Minute of Angle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">Tossing the .047" completely out of your figuring puts one off by under 1/2" at 1000yd. If anyone here can distinguish and hit two objects 1/2" apart at 1000yd, my hat's off to ya.

KISS = "Let's keep things in reasonable proportion, folks...".

Greg </div></div>

The percentage difference between shooter MOA (1.000” @ 100 yards) and true MOA (1.047” at 100 yards) is 1.000/1.047=.955 or 95%.
Let’s say your ballistics need 38 true MOA elevation for 1000 yards
So the difference into shooter MOA @ 1000 yards would be…
38 true MOA*.995= 36.29 shooter MOA (what an IPHY turret moves)
38-36.29=1.71 MOA short of solution for true MOA
So..
1.047*10=10.47” (inches low at 1000 yards per MOA)
10.47*1.71=17.9” round off to 18” low at 1000 yards (difference between true and shooter.)

Greg, it is 18” at 1000 yards not .5”, this will take you out of the 10 ring in your F-class you love so much

 

[Sterling Shooter]

Re: Minute of Angle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: urbancamo</div><div class="ubbcode-body">

Let's see if you figured it out. The firing line is 600 yards to target and line of sight is horizontal. There's a full value left to right cross wind raising dust and blowing loose paper at mid-range. Using your wind formula with a correct constant of 10 how many quarter minute clicks of windage will you need to take to get a good hit? If you favor rather than taking clicks how many inches will you hold off. Try to answer without using a ballistics chart. All you need to answer is an understand of wind velocity, zeroing/MOA, and wind formula concepts. Knowing this stuff is essential to good shooting. Answering this question will take maybe 4 seconds of math you can do in your head. </div></div>

I have a feeling i'm gonna get torn apart after posting this, but this is what I have learned about my rifles ballistics. Keep in mind that I have not tested any of the formulas yet as I have not received my scope back from Luepold yet.

My rifle at about 600 yards with, according to your description, a 20mph full value cross wind will be roughly 19.5 MOA or 78.15 clicks. Sterling Shooter will you please explain how you would go about that calculation?[/quote]

First, average the wind-raising dust and blowing loose paper would give you an 8 to 12 mph wind. Next, take distance to target 6(00) X wind average of 10 mph and divide by the constant = 6 MOA (24 quarter clicks), or about 36 inches of favor. Remember, I provided the constant, and it may not exact for your bullet/velocity.

 

[Greg Langelius *]

Re: Minute of Angle

Jeez, no wonder I can't find the X ring...

But serially..., I haven't been shooting 1000yd F class in going on two years. Doing the FV200 stuff that STP's running at our home range, and I'm enjoyin' heck out of it.

Of course you're right. My comment referenced the .47" difference between 1MOA at 1000yd and my 1" per 100yd quickschtik.

BTW, my .260 makes 1Kyd with between 28 and 30MOA.

Greg

 

[urbancamo]

Re: Minute of Angle

Sterling Shooter: so first off I guess I need to learn to read the wind. Secondly, how do you determine that constant.

 

[Sterling Shooter]

Re: Minute of Angle

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: urbancamo</div><div class="ubbcode-body">Sterling Shooter: so first off I guess I need to learn to read the wind. Secondly, how do you determine that constant. </div></div>

Your bullet's BC will essentially determine the constant for the distance you're shooting. I use the constant of 10 for my Service Rifle in competition at most any distance with either the 77 grain Sierra or 80 grain Berger. 10 BTW is not the correct constant but it's easier to do mental math with that number than let's say a constant of 9 or 11. No, it's not exact but neither is my notion for wind velocity. In other words, it's good enough. I think, if you're shootin' a .308 or .223, you could use a a constant of 10 for most any bullet/velocity/distance with good results.

 

[marduk185]

Re: Minute of Angle

lindy i can never make jbm match my trajectory played with the inputs a long time and it wouldnt give me what the field dope was. maybe im just a tard?