Books on reading mirage.

Dogleg

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Can anyone recommend a good book on reading, dealing with and using mirage for long range shooting? I feel like I'm getting too dependant on wind flags for speed and direction, and they aren't much help for target displacement.
 
There can be time when reading mirage can be a valuable tool but this is more commonly the case at short range. In my limited experience, target image displacement in a running mirage, while visble, is barely significant (less than 1/2 moa). Target image displacement due to shifting but nearly-stationary layers of air of varying density and be quite significant ( up to 1 moa, maybe more) and, what's worse, may be undetectable unless you just happen to be watching during a shift.
At long range, the use of mirage may or may not be of any value because you only see the mirage within a shallow field due to the limited depth-of-field of the high powered scopes. In effect, it is like watching one windflag located next to the target.
I have had days where mirage was a good indicator and the flags were not but this was generally due to poor flag placement or, more likely, pure happenstance. Using a spotting scope focused half-way out (don't forget to watch above the line of sight) can help if the flags are not telling what you need to know.
On my own 300M range, I have six flags (simply surveyors tape on a stick) with three of them located between 33 and 60 meters from the bench (they double as range markers for rimfire silohuette practice). The other three are located at 150, 200 and 250 meters (roughly) and I use mirage only as an aid to estimate velocity. This works well enough for me that I am seldom too far off. Of course, I am familiar with the range and am frequently baffled by wind patterns at unfamiliar ranges (in addition, there are those who will say I am simply not too bright and I have had results which make it hard to argue against this!).
 
Best single reference is The Wind Book for Rifle Shooters by Linda Miller and Keith Cunningham. Prone and Long-Range Rifle Shooting by Nancy Tompkins had a good chapter on wind.
 
Definitely agree with the above 2 books.

Google Army Marksmanship Unit... some good stuff there too but pretty basic.

Besides knowing what and how to use mirage, you have to see it and here there are better optics for the tasks.

Jerry
 
I learned to read mirage and flags as a TR shooter, so I hope my frame of reference makes sense and is helpful to you. This requires a secondary spotting scope so you can dial back the focus without any detriment to aim that would occur if you tried this with the rifle mounted scope.

On a square KD range I would always set up the spotting scope so the top of the next closest berm was at the bottom of my field of view, eg I am shooting at 600 so I get the top of the 500 berm in the bottom edge of the field of view and the targets are in the center. I first focus on the targets and then dial back the focus until I see the blades of grass in sharp focus on the 500 berm.

Now any mirage I see will be wind patterns at that distance for the most part. I choose a close up distance feeling that wind closest to the muzzle will have a greater affect (in most conditions for the ranges I shoot at ) on the displacement of my shot.

David Tubb described mirage patterns like looking at water traveling through a glass pipe, try to imagine the change in the flow of the water as someone turns up the tap and then turns it down. A boiling mirage looks like just that, the mirage will appear to "boil" and flow more or less straight up. You kind of look at your blurry target image "through" the disturbance caused by the mirage patterns. The target will be hardest to see during a boil. A clear sunny day allows you to see the most mirage, where a dull overcast day usually makes it more difficult to see.

Often a change in mirage will occur before the range flags show the same change, kind of giving you advance notice of a change in wind.

Shooting in pairs I would often see watch what I thought was a change in mirage and what it did to my partners shot, both whether they adjusted for what I thought was a change or if it moved their shot in the direction I thought it would. Even though i didn't know how much correction they may have added it confirmed that they saw something too and made a change accordingly.

You can even experiment on your own and fire shots with no adjustment in changing mirage conditions and see how much the shot is moved.

Hope this helps.
 
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