Range Report The Wind and My Sore Thumb

[Wheres-Waldo]

I think most shooters can agree that the wind, in some aspect, is a bit of a sore thumb in their collective skill as a shooter. I certainly feel this way and I would like to better understand the wind, but more importantly, how we can read and compensate for it.

I have a basic understanding of what wind does to my bullet and how to adjust for it, but my basic understanding doesn't usually get the job done. Wind, in my opinion, is a bit of a butterfly effect condition and is unlike some of the constants in shooting; such as, gravity and our compensation with elevation or angle fire and our ability to implement a cosine into our range to produce a relatively concrete solution. In addition, altitude and barometric pressure are easy enough to shoot in by keeping tabs on our station pressure.

Wind is not constant, and the *Full Value/Half Value x Dope for X Range @ X Speed rarely plays out in the real world as I see it.

When was the last time you were shooting at distance with wind blowing in ONE direction the FULL distance from you to your target? About 7 years ago for 30 seconds? Me too.

It’s easy enough to plug in wind from 9 o'clock at 5MPH into your calculations, but I feel it’s not accurate, mostly because more often than not, it does not result in a hit. A 5MPH wind from 9 o'clock at 700-1000 yards (with a 1000 yard target and no wind until 700) will require different dope than a 5MPH wind from 9 o'clock at 100-600 yards and no wind from 600 to your target.

As previously mentioned, we are all familiar with the significance of direction and speed, but what about distance from shooter, span of the wind, and distance from span to target? What about how a close span of wind is affected by a down range switching span?

I've never seen any literature that delves into wind to this degree. I, for one, am quite curious.

Whether anyone has any write-ups on this or any pertinent information or if all of this is completely far fetched, I'd appreciate some well founded advice.

 

[Killer Spade 13]

Re: The Wind and My Sore Thumb

The wind changes.

 

[Leaddog]

Re: The Wind and My Sore Thumb

Interesting you didn't mention mirage. Mirage is your friend and can show you a lot of what the wind is doing. Do you use a spotting scope focused at about halfway to your target? Are you paying attention to the wind conditions closest to your shooting position? Wind is variable to your target. Do you see your trace? Valuable info there, too.

 

[Lowlight]

Re: The Wind and My Sore Thumb

The problem is exactly what Leaddog is saying, talking as if everyone is shooting on a manicured square range, Not everyone is and what works on a square range doesn't work the same in a field setting.

Mirage is not always visible, especially this time of year, or in the mountains and hills, you need a 2 degree C change in the layers of air, or between the air and the ground. What happens when there is no difference halfway between the shooter and target.

Also terrain features, many of which are not found in and around a square range. Terrain has a very big effect and can change the direction and velocity at the shooter, mid range and at the target. It moves wind in a way square range techniques don't work. Even measuring wind at both the target and the shooter, the solution can be wrong because the terrain is effecting mid range that cannot be accounted for.

Square range solutions only working on a limited number of square ranges, wind is not straight, not constant and not predictable, especially in the field.

 

[Kevlars]

Re: The Wind and My Sore Thumb

So what you are saying is its not a video game and that not every variable can be accounted for. It takes experience, patience and practice...

 

[Killer Spade 13]

Re: The Wind and My Sore Thumb

Yep, that's pretty much what the man said.

 

[Lowlight]

Re: The Wind and My Sore Thumb

I can post it again, but people would probably get tired of seeing it,

But in the online trailer video, the wind changes direction 3 times in 20 seconds, with the initial wind blowing across between myself and the target full value, it changes slightly appearing to come from 5 O Clock then rapidly moving as if it was coming from 1 O Clock, again 20 seconds of real time video, and that is just the start. The smoke was tossed down the center of the valley, the shooter on the hill 600 yards yards from the valley floor, the target another 200 yard heading up the opposite hill... all three areas feel the wind in a different way because of the terrain and all three values have a different downrange effect, of which accounting for becomes very difficult. especially if you were asked to shoot on command without sighters.

Mirage at 9000ft is bit difficult especially because the Max ord of the round between the target and shooter is hovering out in space easily a few hundred feet above the valley floor where someone would need to glass to see the mirage as the air temperature will not give you a mirage that far above the ground. You need that separation layer.

In a word, it's not as cut and dry as laying on a square range, getting on a spotter and observing the Mirage against the cut grass then comparing it against the flags lining up along the range. There are too many variables not seen or deceptively indicating one thing, while the actual downrange effect is something completely different.

Is the mountain / hill blocking the major of the wind while still acting on the shooter, is the valley funneling the wind increasing the speed, are the trees blocking the effects mid range and beyond, all this matters.

At Thunder Ranch I have seen a perfect mirage running down the center of the valley on the shooter's side of the target, but the wind had no effect at all because 3/4 of the bullet's flight was being shielded by the hill the shooters were on. The guys were taught to read mirage, which they did successfully, unfortunately it was a waste of time because the terrain overrode what it said. Those who ignored the terrain missed, while those who held center hit time after time

 

[Leaddog]

Re: The Wind and My Sore Thumb

I'm with Lowlight on this one. If there is one variable that is always variable, it is the wind with terrain playing a major factor.

While many of us shoot 'square' ranges and golf course like venues (myself included these days), there are those that make their living shooting in rugged territory. With good wind/mirage reading skillsets, terrain takes it to a higher level. Can you visualize what the wind is doing around hills, through valleys, many times in barren landscapes with little or no natural indicators? Can you see the no wind zones, the wind disturbances and eddys, the Venturi effect slicing through your field of view? This, gentlemen, is what separates the weekend warrior from a true marksman.

 

[Wheres-Waldo]

Re: The Wind and My Sore Thumb

So Frank,

I understand that terrain is as influential on
wind as anything. What I am trying to get a
grasp on us not how complicated
and ungraspable a concrete wind call would
be in field conditions, but how to make even
a rudemetary call that's more than one value
with one speed the full length of the shot.

In your video you do a lot to show how
ever changing wind conditions are, but is there
not a basic method for valuing wind based
on distance as well as direction and speed
or how much a distant switch
wind might negate a closer wind?

 

[Greg Langelius *]

Re: The Wind and My Sore Thumb

Imagine a pool table.

When it's flat and level, the ball rolls straight and performs as would a bullet in a calm wind condition.

When its flat and tilted laterally, the ball follows an increasing curve toward the downward side, and performas as would a bullet in a constant wind.

When it's not flat, but conforms to random hills and valleys, the ball tends toward the valleys, and performs as would a bullet in winds which vary along the trajectory. Any local headwind/tailwind components are also acting to alter the basic velocity degradation, similar to the ball rolling up and down the hills.

Finally, all these tables are marginally higher at the far end, the ball loses some of its forward momentum, and performs with naturally decreasing velocity. A headwind makes it appear as if the farther end was raised very slightly in combination with the basic slope, and a tailwind makes it appear as if the farther end was lowered very slightly in combination with the basic slope.

Updrafts and downdrafts do occur. While their effects should be obvious, their presence and strengths are often very hard for me to detect.

There are other forces, like spin drift and coriolis, and they can also be depicted as deviations from the flat, level table scenario, but their effects are usually less obvious. I don't shoot any more in situations where these effects are significantly apparent, and I don't really give them a lot of thought nowadays.

Coriolis imparts an effect similar to gently, steadily rotating the table around a vertical axis while the ball is rolling; and spin drift acts as if the table were being slowly raised along one side during the ball's travel.

Greg

 

[sharac]

Re: The Wind and My Sore Thumb

I remember seeing some manuals (US army i think) where the wind effects of various terrain types and buildings/obstacles were described. The best way to imagine wind is to use water analogy how would water flow if it were running instead of invisible air.

What i do is take my kestrel out when walking/hiking and measuring guessing trying to imagine the flow of air and i guess in several years of hiking i will get to a point where i'll be comfortable telling my grandkids some smart stuff old farts are supposed to tell

... Seriously though observe and learn and instead of chatting about latest gizmo with fellow junkies try to ingrain in your mind conditions, dope required, windage dialed etc...

PS: Just to add. Being in a hilly country (Alps here and not a lot of flats) also complicates matters as bullet path is an arc and sometimes flow of air can be totally reversed even in such small (~10m depends on distances and caliber of course) vertical distances. And if shooting across depression in terrain even funnier results might manifest.

 

[Lowlight]

Re: The Wind and My Sore Thumb

It's the Art Department vs the Science Department. The Science Department is the information from the shooter measured with an instrument, the Art department is how you apply that information across the entire flight to the bullet.

On a Square range you use all the available information and apply it based on the combination of indicators around you to include what other shooters are seeing. If shooter A fires and the dust blows that is a useful tool.

Remember all wind calls begin at the shooter, we feel it, hear it, then see what it is doing around us. This creates the baseline for the estimation. The more experience you have the further downrange your skills will move.

I have some personal rules I use, for instance on that flat range, for a 1000 yard shot, I will add in for Max Ord. A 6 MPH wind reading might become 8 MPH, because of the TOF and height the bullet will reach. At altitude the same reading would be reduced to 4MPH to account for air density.

With terrain, you have to look at everything, then I would use the ballistic computer set on multiple winds as a baseline. Each segment of the shot is its own and is inputted independently of the others.

So, short answer, there is no formula, other than "Believe the Bullet" it has the final word and will tell you what it needs. This is why we focus on recoil management, the fundamentals, we don't rely on a spotter to tell us what happened downrange with the shot, but we endeavor to see the results of our own shot so we can correct it. We know better than anyone what we did during the shot so we are the best judge to fix it, by believing the bullet reading the reticle and adjusting.

When the winds are such it changes shot to shot the best we can do is attempt to find the pattern and get in front of it. That is the most difficult.

 

[kraigWY]

Re: The Wind and My Sore Thumb

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">The best way to imagine wind is to use water analogy how would water flow if it were running instead of invisible air.</div></div>

Sharac has a good way of explaining it. WATER. Check out a mountain stream. Notice how rocks, deep, shallow, etc, affects the flow of water.

Wind is no differeent.

 

[PeterN]

Re: The Wind and My Sore Thumb

Good info. I shoot regularly at 600 and 800. Two or three times a year I shoot at 1000. All on flat terrain where there is generally a readable mirage. I find that my wind reading at 600 is better than at 800 an way better than at 1000. Probably not a surprise.. The longer the range the more difficulty I have in picking up the cyclic pick ups and drop offs. Likewise I have the same problem with the subtle changes in direction. The frustrating thing is that I have been getting better at the shorter distances but do not see any improvement in my longer distance reads. I know I don't shoot 1000 often enough to build a meaningful experience base but I shoot 800 at least weekly and I see little improvement at this distance. Am going to print this thread, keep a copy in my logbook, and keep pulling the trigger.