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What value do you give the wind on the angles?

  • Half Value

    Votes: 12 13.3%
  • 3/4 Value

    Votes: 8 8.9%
  • More refined, like 3/4, 1/2, 1/4...

    Votes: 60 66.7%
  • Other

    Votes: 10 11.1%

  • Total voters
    90

CavScout85

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  • Jan 22, 2018
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    I'm trying to get better at calculating my wind holds when the wind is something other than full value, and I have seen wind clocks that use half value and 3/4 value for the wind on the angles.


    halfValue.PNG 75 value.PNG

    Which of these do you use, and feel free to explain why, or do you use more refined values?

    Is it worth trying to break the wind down into 3/4, 1/2, 1/4, or is that lost in our ability to read the wind that well, or always changing conditions?

    Thanks guys.
     

    perttime

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    My old reference, John L. Plaster 'Ultimate Sniper', suggests 75% values at 45 degrees off the bore line - and 50% at 30 degrees off - as more refined values.
     
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    plidenbrock

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    Not sure I agree with either diagram. The second one is closer in value to what I use, but giving 3/4 wind value for that broad a swath (up to one o'clock) seems a bit overly aggressive.

    Agreed.

    Between those two only, for quick and dirty, the second one is better. But imho taking cosine values is not that difficult and gives exact values. If my understanding is correct, at 45*off target (10:30 or so), the true correction is something near 71% or so. 50% value occurs at 30* off target (11:00 or so, as each hour on the clock face is 30*). At 60* off target (10:00 or so) exact correction is just over 86%.

    Lowlight's illustration is the one I'd use hands down if you're not mathematically calculating the values.
     

    Rocketvapor

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  • Dec 10, 2018
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    I also like Lowlight's diagram for the quick and dirty.
    Heading to Pascagoula in a little while for another 600yd shoot.
    Looks like a 10mph wind from the west with a little variability to the SSW (range points east), 29.9inHg, 70%Rh, and temps in the mid to upper 50's.
    Gonna dial in 11.5 up and if the wind doesn't switch around much expect to use 0 to 25% for an MOA or less windage.
    (22N, 88ELD, 2880)
     

    bax

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    FWIW, in my experience a direct headwind is harder to suss out than a wind coming from ahead left or ahead right. It seems like the slightest fishtail will give me about double the horizontal I was expecting. The POI shift to the right or left isn't great but the fishtail seems to give me both at the same time. I have had similar behavior with a 6 o'clock tailwind - the amount of horizontal is less but the effect is similar. Has anyone else noticed this?
     
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    Terry Cross

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    Would this work for getting YOU good info for YOUR ammo with different wind direction?

    Why not get your Kestrel with AB or other proven ballistic solver with an accurate profile of your rifle/ammo.
    Decide if you want to turn off Spin Drift, Wind Jump, Coriolis, etc.
    Build you a diagram or chart with a couple of wind speeds and your clock face drawn in.
    Run the info through your device and go to the "range card" type display and write down the numbers for each wind direction.
    When complete you should have a very accurate chart that models real data for your rifle.
    After getting all of that crap written down, you could streamline the numbers into some type of user friendly card or data book sheet.
     

    christopher.dow

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    Apr 28, 2017
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    OK, well, shit. I'm going to jump into the ring with the Big Dogs. I hope I make it out alive. Somebody ring the bell if I stop moving, please.

    I'm pretty new to long-range shooting, but I've been doing pretty hard math since before @Lowlight went to basic, and I've been writing code since he was in Scout Sniper school. I'm formally trained in Physics. I'm very familiar with JBM's published code because I have my own version of it I use for things like replicating AB's WEZ modeling, etc.

    First the thing about Physics is that if you ask a physicist how long it will take for a boulder to roll down a hill, he'll start with, "Imagine a perfectly spherical boulder on a frictionless inclined plane". If you ask him to compute wind drift, he'll say, "Imagine a spherical bullet on an infinite Euclidean plane with a wind vector that is constant". That's because once the real world gets involved, the math gets super hairy. Wind roses are trying to give you an answer that is like what you'd get from a physicist or, rather, the particular type of physicist called a ballistician. The thing is, all the wind roses published in this thread are wrong. Terry's advice is better, but way too much work, in my opinion, because you can get the "physicist" answers with a spreadsheet where you compute angles and sines. Here is a link to the spreadsheet I used. Of course, it's really important to know how all this shit works and be prepared for your electronics to go down. I make electronics. That's why I know they will go down. Hell, you might just forget to pack batteries. Or the stage may not allow electronics. In that case, you really need to know what the electronics are doing. That's where computing all this and writing it down becomes critical. It's also where an angle indicator or a cosine indicator (because it's cosine for the drop when shooting at an angle--not the sine), as well as a mil-dot master or equivalent become important.

    Wind drift is computed by multiplying the sine of the angle between the direction of fire and the wind angle by the full-value correction or:

    sine(Wind Heading - DoF Heading) * (correction for full-value of wind speed)

    It's just that simple. So, it's pretty easy to figure out the angles on a clock (each number is 30 degrees) and compute a bunch of sines. However, when you do that and you overlay it in the "half value" wind rose, you see (as @Lowlight did) just how seriously fuck-brained it is:

    fuckbrained rose.png
    Really? 4.25 o'clock? Is anyone really going to get that right in the field? Under time pressure? Also, note the following:
    • "No Value" ranges from 26% left to 26% right in a very narrow angle.
    • "Half Value" ranges from 26% to 79% in what is still a narrow angle.
    • "Full Value" ranges from 79% to 100% to 79% in a pretty wide angle.
    My conclusion is this rose works for full value winds and not much else. Remember how people talk about how a full tailwind or a full headwind are the worst? This is exactly why. Yeah, they can be switchy, but all wind is switchy. The difference is that the changes in direction at those angles have vastly greater effect on the trajectory of the bullet than they do in the "full value" range.

    Which is not to mention the shooter in the middle of that rose isn't squared up behind the rifle. Poor fundamentals. Don't listen to him. (Yeah, I know back then everyone used a sling and that's the right way to shoot prone from a sling).

    Now, let's look at the "3/4" rose:
    75 rose.png

    Again with the half o'clocks!
    • You have a swing from 11.5 o'clock to 12.5 o'clock that is 52 percentage points
    • In the 60 degrees between 12.5 o'clock and 2.5 o'clock, you have a swing from 26% to 97%
    • You have a narrow range of 15 degrees from 2.5 o'clock to 3.5 o'clock where you go from 97% to 100% and back to 97%
    Again, good luck doing all that arithmetic in your head under time pressure!

    Now, let's look at the rose that @Lowlight made:
    Corrected Lowlight.png

    OK, so he isn't totally off. In fact, I'm pretty sure I've heard him say he rounded the percentages to make his rose easier to use. However, look from position 15 to position 1. There's a swing of 76 percentage points. Being a little bit off in this area is a big deal. Can you judge an angle between your DoF and the wind to better than 15 degrees? Well, that's good, but even if you get down to 5 degrees, you're still playing with a LOT of variance. You swing between 38% and 92% in 45 degrees. You better be good at this. I'm sure some of you are. Congratulations! That's why you're winning matches.

    So, what's the solution?

    A: Use either the 3/4 value rose or the one from @Lowlight to do an estimation, practice sound fundamentals so you can see your splash (if conditions allow), and then use the calibrated ruler three inches in front of your face to make a correction. But that doesn't work in all situations because:
    1. You're at a match where you're not allowed to shoot at the same target twice, and the DoF varies a lot in the stage.
    2. You're shooting at an animal and aren't suppressed.
    3. You're shooting at a human who doesn't live by inshallah (or, "I don't need to duck because if it's God's will I get killed, I'll get my 72 virgins and finally get laid") and will therefore hide behind a rock when he hears the first splash.
    B: Get a good reading with a Kestrel and enter the relevant data into a ballistic computer. I used to use a ConX/Kestrel setup and now use a TerrapinX/Kestrel setup. In the match I shot Sunday, I had pre-printed labels with the target locations and distances for my arm band. I lazed every target while I was in the hole and wrote the elevation and windage (and corrected distance if I saw a difference from the match book) on the label and dialed those numbers. I was the worst shooter in my squad by a good margin (I really suck at positional shooting), but got the highest score in the squad on the stage that had the worst wind. One of the targets was at a 15-20 degree angle down. The Kestrel/TerrapinX accounted for that, and several of the other shooters were high. So there's that.

    C: Combine A&B by using a rose if the wind is close to full value, and use a Kestrel if it's not.

    Lastly, a little bit about the "physicist" answers: We don't shoot "perfectly spherical bullets" We shoot G7 bullets. So, even with a perfect wind and DoF vector (meaning both the velocity and direction estimation are perfect), we are still not accounting for the full value wind moving across the length of the bullet and the no-value wind pushing at the tail or the tip of the bullet, which each have different drags. That still doesn't change the solutions above.
     
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    lowlight

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  • Apr 12, 2001
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    I was actually just getting ready to make a new Rose,

    One that is closer to what @christopher.dow has I wanted to simplify it even more

    I want to get closer to the Head and Tailwind area that Chris shows at 25% give or two

    You have to use easily remembered numbers so when you start looking at 38% it's easier to make it 40 or 45% vs saying 38% so yes stuff gets rounded all the time. You have to in order for people to remember it.

    I think the biggest error is the "No Wind Value" sections on the rose as way too big and completely wrong, if you are off center by a little there is a drift, depending on the wind speed of course. But I wanted to put "Edge of Target" or something similar like E for Edge at least.
     

    christopher.dow

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    I was actually just getting ready to make a new Rose,

    One that is closer to what @christopher.dow has I wanted to simplify it even more

    I want to get closer to the Head and Tailwind area that Chris shows at 25% give or two

    You have to use easily remembered numbers so when you start looking at 38% it's easier to make it 40 or 45% vs saying 38% so yes stuff gets rounded all the time. You have to in order for people to remember it.

    I think the biggest error is the "No Wind Value" sections on the rose as way too big and completely wrong, if you are off center by a little there is a drift, depending on the wind speed of course. But I wanted to put "Edge of Target" or something similar like E for Edge at least.

    Since all I did was point out what's wrong, here's why I think your current one is the best rose:
    • It's in 16/ths instead of 12ths. The English measurement system was created because humans are good at halving things. A 16th is a 1/2 of a 1/2 of a 1/2 of a 1/2.
    • The errors in your rose are provably smaller than the errors in the others.
    • Your arrows are more affirmative, in that they indicate the direction the shooter should care about. In the other ones, the shooter has to work in between the arrows, and I see a lot of room for mistakes with that.
    38% vs 50%, 71% vs 75%, and 90% vs 92% are obviously not that big of a deal, and making the rose usable is really important. It makes sense to sacrifice some precision for usability.

    Another point I wanted to get across was that I disagree that head/tailwinds are "switchier" than crosswinds. The math shows the real problem is that at those angles, errors in estimation have greater consequences.

    I think a new rose that specifies when to hold edge of target vs. when to compute would be very valuable. You may want to indicate where it's advisable to use a computer. That's the most valuable lesson I took from the exercise: Use a computer between 10 o'clock and 2 o'cock if you can.
     
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    lowlight

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  • Apr 12, 2001
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    Head and tall winds are the hardest because they are never consistent.

    The issue is, people don't understand each second counts with a head or tail wind because they constantly switch between Left and Right, so guys will see Left, Left, Left, then they get on the gun and hold left and meanwhile the wind switched to the Right Side and they miss. You have to really chase it and refocus back on the wind through the scope to double, even triple check the direction.


    It's always moving between the two and bounces from 0 to say 25% however it never stays to one side of 0 or 12 O'Clock, it varies.

    Wind in software and in a lot of people's mind moves like a straight line at a certain velocity. The software only understands this unless you have one that includes multiple wind zones where you add in more than one variation. I mentioned this in the podcast this week, think of it this way:

    Sitting on a beach we are timing the waves as they roll in. The software sees each wave as being identical, not only that they see each subsequent wave arrive on a very specific timeline. Think about it like a 1000 yard perfectly straight line with an equal velocity across the entire course. This never happens, we don't shoot in a vacuum under the same conditions every time.

    A head and tailwind amplify this problem by not only changing speed but the direction, and since the direction is now working on a narrow path any small change left or right will appear larger.
     

    THEIS

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  • Nov 27, 2017
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    Hi,

    So..how much of our wind reading errors are based on not being able to monitor; which leads to not being able to calculate for the vertical wind shear since all the commonly used detection tools only monitor the horizontal wind shear; even then we can essentially input human error into that horizontal reading by not having the detection equipment placed properly. Hold that kestrel wrong and watch the horizontal wind speed reading decrease.

    The lack of vertical wind shear detection and accountability would also make the head/tail winds appear to be the hardest.

    Looking forward to seeing new and improved wind rose.

    Sincerely,
    Theis
     

    lowlight

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  • Apr 12, 2001
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    The vertical component is unnecessary to worry about in most practical shooting and is very terrain dependent

    If you are looking at a flat manicured lawn the vertical component is well within our group size error.
     

    Skookum

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  • May 6, 2017
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    FWIW, in my experience a direct headwind is harder to suss out than a wind coming from ahead left or ahead right. It seems like the slightest fishtail will give me about double the horizontal I was expecting. The POI shift to the right or left isn't great but the fishtail seems to give me both at the same time. I have had similar behavior with a 6 o'clock tailwind - the amount of horizontal is less but the effect is similar. Has anyone else noticed this?
    A couple things could be contributing to this, I've noticed it myself.

    1) When the wind is in your face you are shooting into a condition that may have changed without you being able to see it. So you are basically shooting into a new condition, but the wind change hasn't reached you yet. The opposite with a tail wind, you feel the change, but you are actually shooting into the previous condition.

    2) Light refraction is exaggerating each switch. As the wind moves back and forth, whatever image displacement is present is switchind side to side also.
     

    Diver160651

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  • Feb 7, 2013
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    1) When the wind is in your face you are shooting into a condition that may have changed without you being able to see it. So you are basically shooting into a new condition, but the wind change hasn't reached you yet. The opposite with a tail wind, you feel the change, but you are actually shooting into the previous condition.

    I’m going to go on and add a bit to the above. I find the tailwinds for most people, are much harder than headwinds because we walk through life using our face nose, ears and eyes as weather vains. When faced with a Headwind we’re pretty good at feeling the directional changes even if a bit delayed. We loose most of that with a tailwind when the wind is blowing and hitting us on our jackets and our faces are on the glass.

    Most people apply the no-wind value to far off the centers, headwind or tailwind.
     
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    DIBBS

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    I would be happy with a draft printable copy of the new /modified rose, as I am struggling at a relatively new shooting spot for me with a tailwind. I am not picking up visible indicators from vegetation or mirage, and have experienced apparently strong updrafts @ an 860 yard target as well as fishtail winds at a 1220 yard ridgeline where we place targets. The struggle for consistent/accurate wind callshas me contemplating creating some smoke or getting some smoke cannisters just to watch the terrain influences and try to get a better read of what the wind is doing, and what the peculiarities are of a couple areas /distances on this range. Good discussion!
     

    Diver160651

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  • Feb 7, 2013
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    terrain influences and try to get a better read of what the wind is doing,
    Unknown-1.jpeg

    What's the wind doing here?

    BTW last weekend match was predominantly a tailwind 12-20; While it is a windy range, it normally is not from behind. The image is from the flat Silhouette range at the bottom left behind Jon's back of the image below.
    Jon.jpeg


    Oh home range is hilly just imaging the bottom of a bolder strewn stream. Shooters hiking to another stage below
    Unknown-2.jpeg
     
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    Diver160651

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  • Feb 7, 2013
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    Example, of ease/speed of mil wind and angles: I use 6mph gun

    FV at 600 .6
    90% I round down .5
    75% round down .4
    5o% .3
    Just off 0/360 .2

    It’s all a guess sense I really don’t know the true wind. It is either an issue because I tolerance stacked or works wonderfully because the error was the other direction. But it gives me a place to start without a Kestrel, or a card.

    Btw use @Lowlight wind rose with your solver you developed mil wind and you might be surprised just how closely it works..

    Caveat being the zero wind value are way smaller than most those charts would have you think
     
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    perttime

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    Getting a reasonable estimate of what the wind is really doing along the bullet's flight path might be much more critical than getting a precise number for what the effect is when a steady wind blows 52 degrees from your front-right.
     

    Diver160651

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  • Feb 7, 2013
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    Getting a reasonable estimate of what the wind is really doing along the bullet's flight path might be much more critical than getting a precise number for what the effect is when a steady wind blows 52 degrees from your front-right.


    That’s we trying to do, but just like movers, we are taking the true angle and true mph out of the wind with our educated combined wind value guess. We then fire the shot. If we are centered up we are using that as the wind speed, if we are not, we use the needed adjustment as the speed. The angle once applied, kinda then does not matter unless wind switches or the AOF changes.

    The wind rose is a teaching and visualization tool, nothing more. Nobody is trying to say the wind is exactly 52* or whatever in the real world. Well unless your “that guy” caught up in his Kestrel, spinning round and round every 20 minutes because he thinks he needs to adjust station preasure at every stage.
     
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    THEIS

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  • Nov 27, 2017
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    Hi,

    @Diver160651 ... In regards to your question of "What is wind doing here".

    I will give it a shot :)..... DISCLAIMER....artistic in nature I am NOT, lol.

    If we take the "Main" wind as purple. It comes downward into the valley. Pools against the mountain side and begins to flow upwards (See Orange). But the orange is actually slightly higher in micro-environment elevation so it collides with Blue downward wind which forces an undercurrent so to speak. That undercurrent takes the easier exit routes (See yellow) instead of trying to go over the mountain side where Purple is pooling.

    Sincerely,
    Theis

    Wind.jpg
     

    MarinePMI

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  • Jun 3, 2010
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    Personally, this time of year, and in that type of dry climate, I'd say based on the shadows, you may also have some thermals affecting the winds. As in, the air is heating up and moving it to the left, off the ridgeline (sun is to the right) and right side is showing right wind because it is hitting the ridge face, even though the prevailing wind may be coming from behind. From this photo, I'd say that tailwind is actually favoring a 5:30 direction of origin.
     

    DIBBS

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    Being a wildland firefighter I have been able to observe for a lot of years terrain influences on wind /smoke and fire behavior. In addition how canyons/gullies/draws/ridgelines affect channel direct and accelerate winds. I have a general idea what "should" be happening when making wind calls , but have a couple places that I shoot that have anomalies that at times stump me. I guess that's what makes this challenging, as if we were able to make first round hits on all our targets, it would get pretty boring...eventually.
     

    THEIS

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    Hi,

    And Add to that...that terrain in itself is a nice accelerator of mechanical turbulence aka Wave pattern LL referred to earlier.
    1545324112801.png

    Sincerely,
    Theis
     

    Diver160651

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  • Feb 7, 2013
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    Hi,

    @Diver160651 ... In regards to your question of "What is wind doing here".

    I will give it a shot :)..... DISCLAIMER....artistic in nature I am NOT, lol.

    If we take the "Main" wind as purple. It comes downward into the valley. Pools against the mountain side and begins to flow upwards (See Orange). But the orange is actually slightly higher in micro-environment elevation so it collides with Blue downward wind which forces an undercurrent so to speak. That undercurrent takes the easier exit routes (See yellow) instead of trying to go over the mountain side where Purple is pooling.

    Sincerely,
    Theis

    View attachment 6989398
    Great ART.. Actually I think I am going to print it and leave it on my desk.

    Truth be told, our squads first station had some 8" and 10" , 1/2 diamonds in that 400-500 range. Diamonds for those that do not know, are really tuff. If your wobble + dope on the obstacle is even .1 in elevation form center, you'll go from 2MOA plate to 1MOA of windage. @THEIS your edits are about how we faired on that FIRST stage -LOL -- Luckily, we learned a bunch and bounced back a bit. The guys that started on our give-me stage, had 4MOA round gongs to get started..

    The wind was blowing solidly 12-20 from about 190° - 170° with the top of the page being 0/360°. We are shooting across I think, 1 to 4 canyons depending on the stage.
     

    MarinePMI

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    The images I have regarding Terrain that comes from the Smoke Jumpers is the best

    View attachment 6989402
    View attachment 6989403
    View attachment 6989404
    View attachment 6989405
    View attachment 6989406

    I have a great document on wind conditions in the field

    That second to last image is exactly what we saw on the Bravo range at Stone Bay all the time. Target positions 2-5 and 45-47 often had null value wind calls when everyone else was dialing wind, due to the tree line on the left (image 4), and the berm on the right. We used to call it "the dead zone".
     

    brianf

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    most usable rosette i ever used:


    1545325896642.png

    not selling a product here its just something i messed with and created over the years. dont want to get in trouble.

    actually made a bunch of prototypes years ago for a wind training tool using a slide rule principal.

    not my real job so i never did anything with it, wife bitches i have a bunch of boxes of crap in the basement that i wont toss because i put so much time into it lol.

    set up a website with some guys that work for me, set up a company for free on line, all just screwing around.

    this was before kestral and ballistic apps had more than one wind input etc.

    but the idea was that you could line up the wind speed from the direction it was coming (rotate the disc) and then just follow the line and get the converted full value wind speed.

    EX. 10 MPH from approx is 7 MPH converted to full value etc. no calculation needed just rotate and look.

    i had it set up that one disc was manipulated for the speed and the other disc was used for calculating the solution.

    patented it and what not, just a hobby that got out of hand...like most things i do.

    anyway, damn thing worked really well.
    was also milspec materials, always though of it as the ultimate backup.

    one side was for calculating wind speed, and the other side was a full on calculator for addition, subtraction, mult, dividsion, angle fire.

    mil to moa, target distance, all the regular crap we use...

    just another shooting hobby expense over the years

    1545325913382.png


    1545326243561.png
     

    christopher.dow

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    most usable rosette i ever used:


    View attachment 6989412

    not selling a product here its just something i messed with and created over the years. dont want to get in trouble.

    actually made a bunch of prototypes years ago for a wind training tool using a slide rule principal.

    not my real job so i never did anything with it, wife bitches i have a bunch of boxes of crap in the basement that i wont toss because i put so much time into it lol.

    set up a website with some guys that work for me, set up a company for free on line, all just screwing around.

    this was before kestral and ballistic apps had more than one wind input etc.

    but the idea was that you could line up the wind speed from the direction it was coming (rotate the disc) and then just follow the line and get the converted full value wind speed.

    EX. 10 MPH from approx is 7 MPH converted to full value etc. no calculation needed just rotate and look.

    i had it set up that one disc was manipulated for the speed and the other disc was used for calculating the solution.

    patented it and what not, just a hobby that got out of hand...like most things i do.

    anyway, damn thing worked really well.
    was also milspec materials, always though of it as the ultimate backup.

    one side was for calculating wind speed, and the other side was a full on calculator for addition, subtraction, mult, dividsion, angle fire.

    mil to moa, target distance, all the regular crap we use...

    just another shooting hobby expense over the years

    View attachment 6989413


    View attachment 6989416
    Your trigonometry is spot on. Well done!

    Is there any place to buy that thing? I have a thing for analog solutions.
     
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    Diver160651

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    I like to keep things simple.. Simple is lets my small pea brain think of the other stuff and ends up being way smoother, thus faster, usually very good for plate work. ELR or legged things especially if you have time and distance are another thing.

    While these formulas work, ONLY really smart guys like christopher.dow might be able to work them thru :)
    Turbulance.png and Comp Fluid Dyn.png

    I prefer to think like a 5th grader. We are looking at the bottoms of streams and rivers when we look towards our targets, we just can not see the wind; only the optical anomalies, particles and effects. If on top of a hill and using a meter, we expect a bit faster, in the valley, slower than what the flight wind will be. Wind shadows tend to be very turbulent on the edges and effect the wind many times their height. The value modifiers of course are the contours, that act like the river banks.
    stream-wind2.png

    I draw with Crayons sorry for my crude illustrations above.. But I would say (past) sponsored as a windsurfer, then latter running the foredeck on a 105, I learned a bunch about wind.. Unfortunately, I still get tricked.

    Check out our ELR target -- talk about switchy winds.

    Edit: While the rotors in the image are a different thing, this still give one an idea of just how much lager wind shadows are than the object. Something we tried to avoid (or tried to do to our competition's boat).
    horns_rev.jpg
     
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    damoncali

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    The way I see it, any esitmate of wind direction is going to be spotty at best. Simply using full/.75 (rounded from .707)/.5 for 90, 45, 30 degrees is plenty fine enough.

    And pay attention to direction a lot more in a fishtail, because the impact of an 11 o'clock to 1 o'clock twitch is WAY bigger than the impact of a 2 to 4 twitch.
     

    davsco

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    so why not just stand parallel to your rifle (which is aimed at target) with your kestrel and see what it says for wind and use that, why involve a bunch of math or gadgets in the equation? i understand this would be less or not useful when looking at downrange wind. wind reading/calling is def my weakness so if this is really dumb please let me know why.
     

    Diver160651

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    so why not just stand parallel to your rifle (which is aimed at target) with your kestrel and see what it says for wind and use that, why involve a bunch of math or gadgets in the equation? i understand this would be less or not useful when looking at downrange wind. wind reading/calling is def my weakness so if this is really dumb please let me know why.
    You don't always have a kestrel,
    1. Not everyone owns a kestrel

    2. Not every kestrel is set up to dope the wind correctly

    3. Not every shot is taken administratively allowing you to stand up and dope the shot

    4. Knowledge is power

    +
    It is slow
    and no way is it telling real the story across Canyons as illustrated in the thread already
     

    DIBBS

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    so why not just stand parallel to your rifle (which is aimed at target) with your kestrel and see what it says for wind and use that, why involve a bunch of math or gadgets in the equation? i understand this would be less or not useful when looking at downrange wind. wind reading/calling is def my weakness so if this is really dumb please let me know why.

    Definitely not an expert on wind calls- correct ones anyways.

    That being said, you can have multiple different wind vectors between you and your target because of terrain influences, the wind at your shooting position is only one part of the equation.
     

    lowlight

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    are you saying kestrels are not that accurate or there is some set up that i likely haven't done, or something else?


    You have to true elevation for your rifle correct, and elevation is a much easier solution than windage, so why would you assume by default the wind is correctly doped.
     
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    brianf

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    so why not just stand parallel to your rifle (which is aimed at target) with your kestrel and see what it says for wind and use that, why involve a bunch of math or gadgets in the equation? i understand this would be less or not useful when looking at downrange wind. wind reading/calling is def my weakness so if this is really dumb please let me know why.

    i get what you saying, problem is we need the gadgets.

    my wind calc disc above was made just for that.

    went to a few schools from top guys and the biggest issue i ran into was no one really told you what to do if there was a:
    1000 yards
    firing position 6 mph at 3:00
    half way 2 mph at 1:00
    and at the target 8 mph at 1:00

    or what happens if you have 2 right winds and 1 left wind

    they all said "you just have to know or shoot for 30 years...", or use the close wind or use the far wind or the wind at 600 yards is the one to look at...

    in my head i called bs.

    ballistics is just math not guesswork, the guesswork is reading the leaves and grass to get the wind speed.

    i designed the disc to take 3 different wind zones (close mid far, could be more or less but 3 seems the best combination of accuracy and speed) and combine them into a single full value MPH that you could use with your data card.

    with the winds speeds above...you use 3.75 mph for your calculation full value wind and i guarantee youll hit.
    we were using 11x17" maidens for all the testing and historical knowledge.
     

    lowlight

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    I have shot in Pike National where the only way to get the correct wind solution is to use Multiple Wind Zones in the calculator

    The problem is, many current Apps used don't include this feature, it's more an advanced thing.

    the Discs above are a very good analog solution.

    The problem with students is the variety in a lot of ways, I can pull out my Nomad with ColdBore on it or FFS and show the students the multi-Zone feature and then work to estimate the values, but it's time-consuming and difficult. Unless it was a one on one class or a specifically designed "Wind" class it's just easier to stick to basic instruction on the subject.

    On square ranges, you don't see the issue, beyond flags moving the wrong way, but that is not really a wind zone issue, that is a local issue like a berm or something. There is not a spike of wind in the opposite direction unless the terrain is causing a backflow like noted in the images above. But the prevailing wind is not reversing, it's terrain.

    So in the mountains, where the prevailing wind can actually turn and bounce off the terrain, that does create issues you cannot always account for correctly in a single zone App.

    If I hit the mountain, the 3 Wind Zones are automatically turned on.
    CB1_Phone_Ballistics_Winds_ON_resize.png
     

    davsco

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    You have to true elevation for your rifle correct, and elevation is a much easier solution than windage, so why would you assume by default the wind is correctly doped.
    i'm not following you. at the firing line (i understand there prob is different if not way different wind downrange) are you saying kestrels don't measure wind speed correctly or am i totally missing your point? thinking i want to at least know the actual wind at the firing line as that seems the easiest to get right?