Moa conversions

[Lcpl Hinson]

Ok so I have 1click moves 1/4 at 100 yards. And 1 click moves 1 inch at 400 correct. How do u know how many behind that. 700 yards how many clicks.

Also my dope card says At 700 yards my round drops -138.8 inches which is -18.9 MOA. If it moves 1/4 inch every 100 yards how many times would I turn it for 18.9 moa. I'm having hard time wrapping my head aroun this.

 

[gstaylorg]

Re: Moa conversions

Here is a picture that might help:

Whether you're using MOA or mil, forget about inches! It will only confuse you further. Both MOA and mil are <span style="font-style: italic">angular</span> measurements, meaning 1.0 MOA is the same angle whether the distance to the target is 100 yd, or 1000 yd. If you try to convert MOA to some arc length subtended at a specific distance, it makes it much more difficult to wrap your head around. Plug your projectile from the dropdown menu and muzzle velocity at JBM Ballistics (link below) along with the appropriate atmospheric conditions, and use the drop values it will give you as a starting point for various ranges. Then determine your <span style="font-style: italic">actual</span> drops at those distances by live fire. You'll be amazed how close the predicted drops can be if your input data is solid.

http://www.jbmballistics.com/cgi-bin/jbmtraj_simp-5.1.cgi

 

[Driftwood]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lcpl Hinson</div><div class="ubbcode-body">Ok so I have 1click moves 1/4 <span style="color: #FF0000">MOA</span> at 100 yards. And 1 click moves <span style="text-decoration: line-through">1 inch</span> <span style="color: #FF0000">1/4 MOA </span>at 400 correct. How do u know how many behind that? And 1 click moves <span style="text-decoration: line-through">1 inch </span><span style="color: #FF0000">1/4 MOA </span>at 700 yards <span style="text-decoration: line-through">how many clicks? </span>
Also my dope card says At 700 yards my round drops -138.8 inches which is -18.9 MOA. If it moves 1/4 <span style="text-decoration: line-through">inch</span> every 100 yards how many times would I turn it for 18.9 moa. <span style="color: #FF0000">(18.9MOA X 4 = 75.6 quarter MOA "clicks"</span>).I'm having hard time wrapping my head around this. </div></div>

I fixed it for you.

The diagram and explaination provided by gstaylorg should do the rest. Just keep your data in MOA and don't worry about converting to inches at any range. I wouldn't count "clicks" unless it was dark and I couldn't see. If you need 18.9 MOA just dial 19 MOA. For example if you were using a Leupold scope with M1 turrets. The dial is numbered in MOA 1-15, each complete rotation is 15 MOA, so I would dail one full rotation, then dial 4 more MOA for a total of 19 MOA, I wouldn't bother counting 76 "clicks"

 

[kraigWY]

Re: Moa conversions

I find it easier to forget inches and deal in Minutes.

Its 1/4 min click......not 1/4 inch.

Or 1/10 Mil not .36 inches if you're using a Mil/Mil scope.

 

[Lcpl Hinson]

Re: Moa conversions

Dude thanks a lot. That cleared it up lol.

 

[Sterling Shooter]

Re: Moa conversions

Did you see that amazon woman? She must have been at least 90 MOA at 100 meters. Do you get an understanding of how tall this woman is? No, of course not. That's because we think about object relationships in inches, feet and yards. My point is, there are plenty of times you will need to convert MOA to inches, or inches to MOA. Holding off with iron sights for wind drift figured in MOA is one example. For this you will need to divide distance to target in yards by 100 and then multiply that factor by needed MOA of favor for an answer in inches. Another example might be making an elevation adjustment on a target which is not seen in MOA perspective. For this you will need to convert inches to MOA by dividing distance to target in yards by 100 and then dividing that factor by inches of displacement.

Now back to favoring for wind in inches, some will say just count MOA on the reticle if using a scope. O.K. but let's get real with it. Imagine an E target at 600 yards and a wind requiring a 6 MOA favor. Can you picture a 6 MOA favor no you can't so you will need to either click or count on the MOA reticle. Both take time. But just favoring 36 inches is fast and easy, no clicking or counting, just a quick 6 times 6 and then a hold off of a very perceivable 26 inches from edge of target.

At any rate, with irons, dot or ACOG you will need to know how to convert MOA to inches and perhaps inches to MOA. In general, and even with a scope reticle graduated in some sort of MOA based increments, it's still basic marksmanship to know how to convert as discussed.

 

[kraigWY]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Did you see that amazon woman? She must have been at least 90 MOA at 100 meters</div></div>

LOL you got me there. I guess I've should have been more clear.

Imagine, looking at the list of the girls on my granddaughters basket ball team which gives their height.

My granddaughter would be listed as 267 MOA @ 25 yards. I could see where that would creat problems.

After ranting about thinking in minutes I should have said it was using the elevation/windage knobs.

When hunting I know the gerth of X animal is 18 inches. With my zero I know I have to hold over 6 inchs to hit where I want to. So I hold over 1/3 of the girth. Easy to do. Faster then math.

Where as I look at a high power target, I think of MOA, I know if I figure each scoring ring is ABOUT one moa.

I guess as SS pointed out, you need to still think in inches. Even using Mil Dots. You need to know the size of the target in inches coverted to yards not MOA converted to yards.

 

[salty dog]

Re: Moa conversions

is you scope 1/4 MOA per "click" or 1/4 inch per "click"? because 1 moa is 1.047 inches at 100 yards and 10.47 inches at 1000 yds and if you're assuming 1 inch at 100 and 10 inches at 1000. when you begin "clickin" youre compounding the error.

 

[Sterling Shooter]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Salt Shaker</div><div class="ubbcode-body">is you scope 1/4 MOA per "click" or 1/4 inch per "click"? because 1 moa is 1.047 inches at 100 yards and 10.47 inches at 1000 yds and if you're assuming 1 inch at 100 and 10 inches at 1000. when you begin "clickin" youre compounding the error.</div></div>

Zeroing to distance it's a concern. Correcting zero from triangulation of group at distance it's moot.

 

[gstaylorg]

Re: Moa conversions

The OP was simply asking about calculating and adjusting for drops for specific ranges. He didn't ask about using different sized objects to range, nor about windage, and it's pretty clear from his post that he was having difficulty understanding the basic concept of how angular measurement relates to drop at a specific distance in order to simply dial his scope. I understand how conversion from angular measurement to arc length at a specificed distance can be important, but you need to learn to crawl before you learn to walk. Understanding angular measurement and how to use the reticle is much simpler without trying to think about arc length until you're more familiar with your setup.

 

[Sterling Shooter]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gstaylorg</div><div class="ubbcode-body">The OP was simply asking about calculating and adjusting for drops for specific ranges. He didn't ask about using different sized objects to range, nor about windage, and it's pretty clear from his post that he was having difficulty understanding the basic concept of how angular measurement relates to drop at a specific distance in order to simply dial his scope. I understand how conversion from angular measurement to arc length at a specificed distance can be important, but you need to learn to crawl before you learn to walk. Understanding angular measurement and how to use the reticle is much simpler without trying to think about arc length until you're more familiar with your setup.</div></div>

Until you're familiar with your setup? Any shooter starting out must acquaint himself with external ballistics, trajectory, zeroing, and wind and weather effects. All of these concepts are tied to sight adjustment. And, to be able to hit a target at a given distance when the adjustments are in MOA increments, a basic understanding for MOA and the value of MOA in inches at distance is necessary. You can't just leave stuff out of the discussion because it may appear to tax the new shooter's brain. Taxing the brain is the way we learn what we need to know.

 

[gstaylorg]

Re: Moa conversions

I agree with you completely...right up to the point someone is having difficulty with something as simple as adjusting the elevation on their scope for a given distance. At that point it becomes necessary to adjust the amount of information given to aid the shooter in getting up to speed with basic scope adjustments before launching into a lot of other data that simply compounds the issue. I've seen the result of over-emphasizing how to convert angular measurement to arc length at some distance here often. You end up with an individual that tries to "think" in inches and feels it necessary to convert everything back and forth between angular and arc length measurements and needlessly complicates many simple shooting exercises that can be accomplished without any conversion whatsoever. I reiterate that if someone really understands how angular measurement works, conversion to arc length at some distance follows naturally. The reverse is not necessarily true and you will find strong evidence of that in posts here on a regular basis.

 

[Sterling Shooter]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: gstaylorg</div><div class="ubbcode-body">I agree with you completely...right up to the point someone is having difficulty with something as simple as adjusting the elevation on their scope for a given distance. At that point it becomes necessary to adjust the amount of information given to aid the shooter in getting up to speed with basic scope adjustments before launching into a lot of other data that simply compounds the issue. I've seen the result of over-emphasizing how to convert angular measurement to arc length at some distance here often. You end up with an individual that tries to "think" in inches and feels it necessary to convert everything back and forth between angular and arc length measurements and needlessly complicates many simple shooting exercises that can be accomplished without any conversion whatsoever. I reiterate that if someone really understands how angular measurement works, conversion to arc length at some distance follows naturally. The reverse is not necessarily true and you will find strong evidence of that in posts here on a regular basis. </div></div>

I find new shooters here wanting answers which will sync to their misconceptions of what's important to good shooting. This is not possible. The OP is confused because he simply does not yet understand the concept period. Attempting to chunk his learning here with a partial reckoning does not address what he needs to know, such as if I'm 3 inches from where I want to be at 100 yards how many clicks do I need to take? If the target had an MOA grid he would of course not need to know anything about converting inches to MOA, however, with any sort of standard target he would indeed need to know how to convert using the formula: distance in yards divided by 100 times inches of displacement equals adjustment in MOA necessary to correctly move impact. Since the shooter has fractional MOA adjustments, he would divide MOA by .25 for answer in clicks. The shooter could I guess avoid conversion by buying speciality targets or by buying targets which in size equal multiples of MOA at distance but then are we not compensating for our own inability to teach. Reminds me of the military 25 meter sight-in target with sight adjustment grid. There's an example of since I can't teach it we'll just let the student get it later, which never happens.

BTW, I'm not ranting at you. I see this stuff everyday, folks wanting to know how to do it. I have so many folks ask me how to do it in fact that I felt compelled to print out a sight adjustment lesson which is straight out of a military curriculum on the matter. Thing is, folks just getting into it do not pick this stuff up right away.

One more thing, there are it seems a whole lot of folks out there who have just bits and pieces of what good shooting is all about. And, these folks may also have a head full of gobbledygook about good shooting passed down from others who actually knew nothing about good shooting but because they at one time pulled a trigger they were wrongfully assumed to know something, like granddad telling his grand-daughter to be sure and focus on the target. Any of these folks who get around to getting some training can be difficult to train unless the instructor initially asks them to abandon everything they know for a moment. Well, it can be a big mess to clean up sometimes. It's why, however, folks coming here are best advised to keep an open mind. Otherwise, conflict with what they think they know and what they really need to know will thwart their progress.

 

[Driftwood]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lcpl Hinson</div><div class="ubbcode-body">Ok so I have 1click moves 1/4 at 100 yards. And 1 click moves 1 inch at 400 correct. How do u know how many behind that. 700 yards how many clicks.

Also my dope card says At 700 yards my round drops -138.8 inches which is -18.9 MOA. If it moves 1/4 inch every 100 yards how many times would I turn it for 18.9 moa. I'm having hard time wrapping my head aroun this. </div></div>

If you want to know what the width of a minute of angle is at any distance, Multiply the MOA by (Distance in yards /100)X 1.047 = Inches

So if you wanted to know how wide an angle 18.9 MOA isin inches at 700 yards the equation would be:

18.9 X (700/100) X 1.047 =138.5"

To find the width of 1/4 MOA in inches at 700 yards:

1/4 X (700/100) X 1.047 = 1.83"

To determin how many 1/4 MOA clicks, you simply divide

138.5 by 1.83 = 75.68 "clicks"


I find it easier to just keep everything in MOA when possible and remember that on a scope with 1/4 minute adjustments I need to multiply the MOA needed by 4 if I were to count.

When using favors or hold overs in inches, feet or yards, I use a portion of the target as a reference and base off that. I would prefer to use my recticle as its a little more precise in which case I would use MILS or MOA depending on the reticle. It makes it nice when your spotter has a spotting scope that has a reticle matching the one on your rifle scope as he can call for precise favors/holdovers in MILS.

If you were my spotter I would prefer you give me a 18.9 MOA or 5.5 MIL holdover rather thand telling me to hold either 138.5" or 11.5 feet over the target, but thats just me.

None of it is really hard, its just important to keep the basic concept in mind. MOA describes a constant angle. Its 1 moa at 100 yards or 1,000 yards. The width of the arc grows as the angle extends further, so 1MOA has an arc that is 1.047" wide at 100 yards and 10.47" wide at 1,000 yards, but its still 1MOA. It takes 4 clicks on your scope to make 1MOA at any distance.

It seems easier to me to have your dope in MOA rather than inches, but if someone tells you to hold 6 inches right of your target, I am confident you could do that using your target as a reference without worrying about converting anything, as has already been suggested.

 

[CleanMoostang]

Re: Moa conversions

Only time I ever cared about inches was when I was first sighting in my scope and doing a box test.

Like others have said, forget inches. They only help when you know the exact size of your target, and when you are 700 yards out, no one will tell you to move an inch to the left or right, they speak minutes and mils.

 

[Sterling Shooter]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: CleanMoostang</div><div class="ubbcode-body">Only time I ever cared about inches was when I was first sighting in my scope and doing a box test.

Like others have said, forget inches. They only help when you know the exact size of your target, and when you are 700 yards out, no one will tell you to move an inch to the left or right, they speak minutes and mils.</div></div>

Sighting in, zeroing, favoring, or holding off it's important to understand conversion since the equipment at hand may require it, such as when shooting an M4 with its BDC sight. Understanding conversions is basic marksmanship. Whether you have equipment, memory, or charts to make conversion moot is not the point. Fact is, if you do not have a reticle marked in some sort of MOA pattern and you are shooting at a known size target at a known distance with less than center placement you will likely make a conversion, simply because the brain does not see the displacement as MOA but rather as inches from center. In high power rifle competition the only reason I do not need to convert is my score book has a representation of the target I'm shooting at with an MOA grid proper for the target's distance overlay-ed to it. If I'm hunting conversion is moot too since I will not likely get a second shot and I am as well not likely to see the missed shot's impact. But, for zeroing for a no wind zero where I will have multiple shots to help me understand my displacement I will convert.

 

[Graham]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">O.K. but let's get real with it. Imagine an E target at 600 yards and a wind requiring a 6 MOA favor. Can you picture a 6 MOA favor no you can't so you will need to either click or count on the MOA reticle. Both take time. But just favoring 36 inches is fast and easy, no clicking or counting, just a quick 6 times 6 and then a hold off of a very perceivable 26 inches from edge of target. </div></div>I fail to see how that would be simpler, or easier, or faster, or more versatile, or more accurate as a method.

 

[Sterling Shooter]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Graham</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">O.K. but let's get real with it. Imagine an E target at 600 yards and a wind requiring a 6 MOA favor. Can you picture a 6 MOA favor no you can't so you will need to either click or count on the MOA reticle. Both take time. But just favoring 36 inches is fast and easy, no clicking or counting, just a quick 6 times 6 and then a hold off of a very perceivable 26 inches from edge of target. </div></div>I fail to see how that would be simpler, or easier, or faster, or more versatile, or more accurate as a method. </div></div>

Perhaps you fail to see it because you do not have much experience with iron sights. What is necessary with irons is optional with optics. In my example I indicate the process which is indeed quick and accurate as learned from iron sight shooting.

 

[Graham]

Re: Moa conversions

I have experience with iron sights. What works with irons is not optional with optics, it's different than with optics. One needs to understand both and not try to force one method to apply to the other.

 

[Sterling Shooter]

Re: Moa conversions

No force being used at all, quite the contrary.

 

[Graham]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">No force being used at all, quite the contrary. </div></div>OK, then will you explain how your method of using inches, that you say applies equally to optics, makes target engagement simpler, or easier, or faster, or more versatile, or more accurate?

 

[kraigWY]

Re: Moa conversions

Lets say you're antelope hunting. You know the girth measurments of the average antelope is 14 inchs. You know that half that is the center of the vitals so that's where you want your bullet to impact.

Your range finder tells you the antelope is 300 yards away. From your balistic tables, you know that your 150 308 Win will drop about 6 1/2 inches when its zeroed for 200 yards.

Half of 14 is 7 inches so all you got to do is hold over half the width of the antelope.

That would be a lot simpler and faster then trying to convert it to MOA or Mils.

Works the same way in target shooting if you know the diameter of the bull. Simply use that for a referance on how much you need to hold with your cross hairs.

Personaly I click when I use irons, and sometimes when I'm using glass. Then minutes come in handy.

 

[Graham]

Re: Moa conversions

That's too much guessing for me, and a lot of math to end up with only a ballpark POI.

It's the equivalent of using a point-blank zero and guessing that the animal isn't so far away that the trajectory would result in a miss if I aimed at the top of the back (which is what I would have to do if I had only irons and no time to dial).

However, if my rangefinder says 300 meters I know my hold is 1.2 Mils. That's exactly where the impact will be. That's exactly where I hold. No 'inches' math necessary.

 

[Sterling Shooter]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Graham</div><div class="ubbcode-body">That's too much guessing for me, and a lot of math to end up with only a ballpark POI.

It's the equivalent of using a point-blank zero and guessing that the animal isn't so far away that the trajectory would result in a miss if I aimed at the top of the back (which is what I would have to do if I had only irons and no time to dial).

However, if my rangefinder says 300 meters I know my hold is 1.2 Mils. That's exactly where the impact will be. That's exactly where I hold. No 'inches' math necessary.</div></div>


Ah yes, the rangefinder. Aids can make things simple, except for all the tables you'd need at hand to understand what to do exactly for any specific scenario. And, although such aids might serve for the purpose of holding a relationship to hit a target, once on target what are ya gonna do to when fractional MOA is needed to center impact? This is where understanding conversions is handy. As alluded to in earlier posts the brain does not visualize things in MOA it sees relationships in inches and thus there's a learning conflict when the shooter perceives he must see things in MOA. Having a chart, table, grid, or whatever is not a substitute for learning how to make a conversion or understanding the concept. If the beginning marksman is taught how to do it at his start when becoming acquainted with ballistics, trajectory and zeroing he will not need advice like that coming from here suggesting that he does not need to understand how to do it.

 

[Killswitch Engage]

Re: Moa conversions

i would think that for the purposes of field and tactical application the moa nearly equal to the correspondng inches of said distance is good enough. why is a conversion really necessary.

trying to spin somones brain out on an moa being 10.47in @ 1000 or just saying 10in is a moot point in the real world. you can't discern or hold a half inch.....even you can't charles. especially with irons.

reading your post above about knowing what 6moa looks like at 600yds and just holding 36"....thats not how i do it and i doubt its how most here do it with practical field application or tactical competitive time does it. i know what 6moa looks like and thats what i dial or hold. i don't really give two shits about inches.

i think you need to go out in the real world off the square range and get you a rifle with a good repeatable optic, learn to drive it well enough that you CAN spot your own miss and correct for it quickly in moa/mil and you will see that conversions are too slow and not necessary.

 

[Sterling Shooter]

Re: Moa conversions

So let's say you've got a wind favor requiring 6 MOA of drift and you're using a TA31F ACOG. Now are you telling me you can visualize MOA at distance, most folks can't. And, with the ACOG the shooter is going to need to know how to convert MOA to inches since he must favor without the benefit of a MOA graduated reticle.. The folks who made the optic know this and that's why their distance markings extend to subtend 19 inches. It's for the express purpose of helping the shooter hold off in an inch concept of which he is familiar. And please, don't insult me about real world vs. square range. Marksmanship basics are the same in any arena. Yet, since you brougth it up, my experience serving as a SDM instructor for about 8 years has impressed upon me how important learning concepts, such as this, are from the start to having the ability to fully develop into a really good shooter.

 

[Killswitch Engage]

Re: Moa conversions

yes, i can visualize moa at any given distance. any shooter spending enough time behind the gun working at distance should be able to do that. i don't care what optic and if it has a graduated reticle or not thats how it works for me. i am using mil based optics now and it works the same way albeit, a learning curve to get your brain adjusted to reference what a mil looks like at distance.

i am not trying to insult you at all. i am making the point that when rounds need put on target right damn now precious time is wasted trying to convert something that really needs no conversion. make your brain think in moa or mil. you of all people should understand the dynamics of riflecraft and how fast it can happen when the shit hits the fan or a timed shot needs let loose. we should be making it cave man simple and anything that requires a "conversion" is simply not it when it comes to quick and accurate target engagement.

 

[Graham]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">Ah yes, the rangefinder. Aids can make things simple, except for all the tables you'd need at hand to understand what to do exactly for any specific scenario. </div></div>It is not relevant to your argument how one determines range or elevation.<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body"> And, although such aids might serve for the purpose of holding a relationship to hit a target, once on target what are ya gonna do to when fractional MOA is needed to center impact? This is where understanding conversions is handy. As alluded to in earlier posts the brain does not visualize things in MOA it sees relationships in inches and thus there's a learning conflict when the shooter perceives he must see things in MOA</div></div>Have you ever used a precision rifle for practical purposes, or do you just teach it?<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">Having a chart, table, grid, or whatever is not a substitute for learning how to make a conversion or understanding the concept.</div></div>It is in the military. They get fast hits without knowing why. And they don't use inches.<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">If the beginning marksman is taught how to do it at his start when becoming acquainted with ballistics, trajectory and zeroing he will not need advice like that coming from here suggesting that he does not need to understand how to do it. </div></div>No one suggested that an understanding of 'why' a hit happens isn't ideal. What was suggested is that an understanding of the practical value of using inches as you suggested does not have wide support for practical use.

 

[Sterling Shooter]

Re: Moa conversions

Since you can visualize what 6 MOA looks like at 600 yards, and that this is what you are going to favor, what does it look like? Since you do not see things in inches what do you see. Just for fun, let's also say you have a simple cross hair reticle, and, for whatever reason you cannot click windage, maybe you don't have the time for that. O.K.

 

[Graham]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">Since you can visualize what 6 MOA looks like at 600 yards, and that this is what you are going to favor, what does it look like?</div></div> 6 MOA.

 

[Sterling Shooter]

Re: Moa conversions

I'll repeat for you. What does 6 MOA look like at 600 yards? What's the visual. What relationship do you see? You can't answer the question without at some point creating a relationship between the reticle and the target which is going to subtend in inches. You know that and you know it blows your argument.

 

[Killswitch Engage]

Re: Moa conversions

no, i am doing the same thing as someone who takes the time to break down to inches what the hold or miss would or should look like. i am just not going down to inches because i don't need to. an moa is moa. i have never had any sights or optics that adjust or are graduated in inches so i don't really see the need to think like that.

is your hold going to be 36", 3ft, 37.692" or 6moa????? 6 seems like a nice simple number in my head...ymmv

 

[Graham]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">I'll repeat for you. What does 6 MOA look like at 600 yards? What's the visual. What relationship do you see? You can't answer the question without at some point creating a relationship between the reticle and the target which is going to subtend in inches. You know that and you know it blows your argument. </div></div>Nope. On both counts.

You've had similar kinds of arguments with Frank, and with others. Usually you change your original analogy in order to call a reply post inadequate. Here you changed your example to a crosshair reticle and an unworkable windage knob. Let's skip the inevitable future progression of posts and take your example to an extreme: Assume no crosshairs at all, just thick 'duplex' posts ending at mid-image and no knobs on the scope. I submit that, conceptually, it makes no difference. A trained marksman can still dispense with inches and inch calculations, and even make accurate visual adjustments to hit the target with a follow-up shot.

 

[Killswitch Engage]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lcpl Hinson</div><div class="ubbcode-body">Ok so I have 1click moves 1/4 at 100 yards. And 1 click moves 1 inch at 400 correct. How do u know how many behind that. 700 yards how many clicks.

Also my dope card says At 700 yards my round drops -138.8 inches which is -18.9 MOA. If it moves 1/4 inch every 100 yards how many times would I turn it for 18.9 moa. I'm having hard time wrapping my head aroun this. </div></div>

my thoughts are referring to the above post this shooter is concerning himself with a drop of -138.8 in and wondering about how to get his scope adjusted for said drop by how clicks and how many moa yada yada. i say he's wasting his time and would be better off not giving two shits about the inches of drop. if the dope calls for 18.9 moa and he is working with a 1/4 moa scope you adjust straight to 19moa and drop the hammer. thats one rev to 15 generally and then to 4 on the knob. why bother your brain with however many clicks and inches that is? it doesnt matter. see how fast that is?

 

[kraigWY]

Re: Moa conversions

MOA Changes; 6 OA at 1000 yards is 62.82 - 6 MOA at 600 yards is 36.69.

Now you have to shoot "right now" when favoring its going to take more time to convert your favor to MOA then just favoring inches.

Lets take my antelope hunting example. Let say you're off on your range estimation and you shoot a foot over its back. (Range estimation errors is one of the biggest causes of misses when hunting antelope).

You know, from spotting your missed shot that you're a foot high, you DON'T know the exact range. You know that the antelope girth size is 14 inches. Using the animal itself you know how much 12 inches is at any range.

Which is quicker, just droping down a foot, or trying to figure MOA at an unknow distance.

Anelope hunting is a perfect example here. Its hard to estimate range because the critters are small, often in grass that comes up to their bellys or higher. If you over shoot, you often get a second shot but you have to do it quick. You undershoot, forget it, with dirt kicks up under them they are history.

We get a lot of out of state hunters out here. I lke just stopping and visiting with them. Most camp on a ridge over looking two valleys (Six Mile Ridge if anyone knows Wyoming's Area 7). We shot an antelope at a distance and try to get an accurate range before the stock. Range estimation varies sometimes 200 yards or more. Without knowing the range exactly, you can't determine MOA. But you don't have to see the know animal to know their girth size is 14-15 inches regardless of range.

 

[gstaylorg]

Re: Moa conversions

You guys are really something (LOL). The OP simply asked about how to adjust his scope for drop. All he really needed was a simple explanation of angular measure so he could go play with JBM and figure it out for himself. Somehow this turned into a contest over who knows more about using iron sights (never mentioned in the original post), windage (never mentioned in the original post), hunting (never mentioned in the original post), holdovers (never mentioned in the original post), ranging (never mentioned in the original post), reticles without hashmarks (never mentioned in the original post), and probably half a dozen other things I don't remember any longer. No wonder the poor guy never posted anything else in this thread. Good job, I'm sure he's all squared away on how to set elevation on his scope now.

 

[Graham]

Re: Moa conversions

It's called Thread drift. It happens.

 

[gstaylorg]

Re: Moa conversions

I know, I'm just sitting here chuckling to myself about how great the drift on this one was.

 

[Graham]

Re: Moa conversions

Note the similarities of my answers with this answer:
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=3452331#Post3452331

 

[Sterling Shooter]

Re: Moa conversions

There are omissions in your argument. When zeroing, when using a simple reticle, when using certain ACOG's, and when favoring wind with such a scope, the shooter will no doubt convert inches to MOA or MOA to inches, since the aiming device does not serve the shooter like others. But the big picture here is the brain does not visualize in angular measurement. Just take the military zeroing target for example. Conversion to MOA at distance has been provided. Why? Because if it were not provided the shooter or coach would need to think it out, and that would be an issue at the wrong time and place. So far, you've just conveniently bypassed this stuff because it does not support your argument. At any rate, my argument is not that a shooter cannot get the job done without conversion from inches to MOA, but instead, that knowledge of inchs to MOA and MOA to inches is basic marksmanship. Having such knowledge allows the shooter to better understand the concept of compensating for the effects on trajectory in general no matter what sort of sight is on the rifle.

When teaching the use of the ACOG, students learn how to calculate wind favor in MOA. But since the ACOG's reticle does not support MOA, the student also learns how to convert MOA of drift to inches of drift. This of course is a necessity with irons too.

 

[Graham]

Re: Moa conversions

Claiming now that you meant something different from what you said before doesn't get you off the hook.<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">But the big picture here is the brain does not visualize in angular measurement.</div></div><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lowlight</div><div class="ubbcode-body">The reticle is a ruler, instead of going down range and measuring the impact distance in inches, you should have used the ruler that is 3" in front of your nose.

The reason you use a Mil / Mil scope is so you don't have to mix measurements. As well, like stated, there is absolutely, positively NO reason to think in terms of a linear measurement.

Who cares how many inches any shot is, you have a self contained system that does not operate on the basis of a linear measurement. While it does have a linear value it is irrelevant to what you are doing. Read the reticle, match the reading to the adjustment and move on...</div></div>Your newest argument is weak because in order to make it you again contradict yourself:<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">When teaching the use of the ACOG, students learn how to calculate wind favor in MOA. But since the ACOG's reticle does not support MOA, the student also learns how to convert MOA of drift to inches of drift. This of course is a necessity with irons too. </div></div><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">At any rate, my argument is not that a shooter cannot get the job done without conversion from inches to MOA, but instead, that knowledge of inchs to MOA and MOA to inches is basic marksmanship.</div></div>

 

[Sterling Shooter]

Re: Moa conversions

There's no contradiction here. You say you visualize in MOA, but most folks on the planet do not visualize in angular measurement but rather in linear terms. It's why I asked the question what does 6 MOA at distance look like. It only looks like 6 MOA when there's a reference to MOA. Without such a reference, you'd surely perceive whatever you are looking at to be X inches, feet, or yards. So, rather than abandoning how things are seen in their environment why not start with this knowledge to get to the destination, especially since it's not the ordeal you purport it to be. One more thing what do you do to range a known size target? Isn't the height or width of the target in inches used to calculate distance to target?

 

[Graham]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">There's no contradiction here. You say you visualize in MOA, but most folks on the planet do not visualize in angular measurement but rather in linear terms.</div></div>Now you are arguing semantics. An angular measurement, when seen through a scope reticle, is seen as linear.

Regardless, there's still no conversion to inches necessary.

Although I never said that I visualize in MOA, it doesn't matter: 1" at 100y is 1". 1 MOA at 100y is 1.047". I can't measure the difference with my eyeball, so I am unable to teach a student to visualize in inches instead of MOA. You said that both inches and MOA are necessary. I am saying that one can use neither and perform the same task equally well.

I put it to you that a shooter is unable to favor in inches unless he uses an exiting frame of reference also in inches. Like Kraig said: He knows (assumes) that the girth if an antelope is 14 inches and that's the unit of measurement he chooses to use as a constant when hunting.

That's my criticism of your method: That it assumes inches and relies on inches. That's simply not the accepted standard of how to do it unless, perhaps, one is shooting at paper in hi-power competition as I did in 1983. Times have changed; so has the knowledge and the equipment.

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">Isn't the height or width of the target in inches used to calculate distance to target? </div></div>This discussion was never about target ranging formulas. However, I'm glad you brought that up, because when ranging a target one need not use inches either.

 

[Driftwood]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">I'll repeat for you. What does 6 MOA look like at 600 yards? What's the visual. What relationship do you see? You can't answer the question without at some point creating a relationship between the reticle and the target which is going to subtend in inches. You know that and you know it blows your argument. </div></div>

I will bite, on my scope which has a TMR reticle, 6 MOA looks like 1.74 MIL, which would be halfway between the 1.5 Mil hash mark and the 2 Mil hash mark. It would look similar through my spotters MK4 spotting scope. For me, this would be a little more accurate and just as quick if not quicker than trying to figure out what 36" looked like on a target at 600 yards.

 

[Sterling Shooter]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Driftwood</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">I'll repeat for you. What does 6 MOA look like at 600 yards? What's the visual. What relationship do you see? You can't answer the question without at some point creating a relationship between the reticle and the target which is going to subtend in inches. You know that and you know it blows your argument. </div></div>

I will bite, on my scope which has a TMR reticle, 6 MOA looks like 1.74 MIL, which would be halfway between the 1.5 Mil hash mark and the 2 Mil hash mark. It would look similar through my spotters MK4 spotting scope. For me, this would be a little more accurate and just as quick if not quicker than trying to figure out what 36" looked like on a target at 600 yards.

</div></div>

You don't need to figure what 36 inches looks like. 36 inches is what it looks like.

Here's another example: you want to hit a block of wood at an unknown distance. At its distance it appears to be 3 mils in width. What information do you still need to hit the target. I've already told you it looks like 3 mils and you've already told me you see things in MOA so it would appear you'd have enough information to hit the target but you don't. You still need to know something else. What is it?

For familiar objects we have already learned that they are likely a certain size in inches, yards, or ft. Take the E target, we know it is about 20 by 40 inches so we can memorize what that would appear to be in mils or MOA at any distance we choose. But at some point someone has had to know the target's constant linear size in inches, yards or feet to understand its appearance in mils or MOA at any particular distance. So, while we may not need to relate to inches to hit a target that is not always true and is therefore not fact. The actual accounting used to properly compensate for the effects on trajectory requires a full understanding of relationships beginning with how we size up things, which for most of us will be in inches, feet, and yards.

One more thing, as students of any matter we learn upon what we already know. It makes sense to capitalize on this in learning about how to adjust sights or hold. And, although a student can bypass learning by having the answer given, such as what a target will look like in MOA at distance, this should not be confused with the student actually having learned anything except for memorizing a chart.

 

[Graham]

Re: Moa conversions

I see some progress:

From this:<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">to be able to hit a target at a given distance when the adjustments are in MOA increments, a basic understanding for MOA and the value of MOA in inches at distance is necessary.</div></div>To this:<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">we may not need to relate to inches to hit a target </div></div>To this (admittedly out of context):<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">my argument is not that a shooter cannot get the job done without conversion from inches to MOA</div></div> And from this:<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">I'll repeat for you. What does 6 MOA look like at 600 yards? What's the visual. What relationship do you see? You can't answer the question without at some point creating a relationship between the reticle and the target which is going to subtend in inches.</div></div>To this:<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">You don't need to figure what 36 inches looks like. 36 inches is what it looks like.</div></div>However, you are mixing concepts when you say:<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">But at some point someone has had to know the target's constant linear size in inches, yards or feet to understand its appearance in mils or MOA at any particular distance</div></div><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">So, while we may not need to relate to inches to hit a target that is not always true and is therefore not fact. The actual accounting used to properly compensate for the effects on trajectory requires a full understanding of relationships beginning with how we size up things, which for most of us will be in inches, feet, and yards.</div></div>Because your argument was never about whether one needs to know the size of a target in order to apply a ranging formula.

 

[SHWILL]

Re: Moa conversions

I think this may help you:


http://www.youtube.com/watch?v=VA2PZBD5Tjg

 

[Sterling Shooter]

Re: Moa conversions

Why not just answer the question. Without understanding what size the block of wood is in constant linear terms, you do not have enough information to know what to do, even if you see the block of wood in mils or MOA through your scope. At some point, to understand what hold off or sight adjustment is necessary in mils or MOA you must first know what the constant linear size for this block of wood is.

SHWILL,

I don't know who you are addressing. I understand MOA and I think most recently posting here understand how to adjust sights which are graduated in MOA increments, as well as favor for wind in MOA and whatever. My point is the sight adjustment concept in MOA is not so self contained that a shooter will always be able to make the correct adjustments without some knowledge of how MOA relates to linear measurement. The only place where MOA stands by itself is when information is given the shooter making gathering of the information moot.

 

[Graham]

Re: Moa conversions

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Sterling Shooter</div><div class="ubbcode-body">Why not just answer the question. Without understanding what size the block of wood is in constant linear terms, you do not have enough information to know what to do, even if you see the block of wood in mils or MOA through your scope. At some point, to understand what hold off or sight adjustment is necessary in mils or MOA you must first know what the constant linear size for this block of wood is.</div></div>That's still not correct, despite the fact that you are now changing your argument to match your position.

However, I'm glad that you have abandoned your claim that a shooter needs inches as a unit of measurement.

 

[Sterling Shooter]

Re: Moa conversions

Well, why not just answer the question?