VBull, thanks for the match information that never makes the record books. Most interesting and was enjoyable reading your post.
Sharps, your starter post put me in the search mode for information on the topic that I can glean from when next season arrives with them squigley lines looking down range at that 600yd target. This range is the longest I have close to home here in south Jersey.
Here's some more Internet words after pounding the browser (emphasis is me) ...
(You need to Login or Register to view media files and links) For that long shot that we have to hurry up, get into position and then are put on hold. Most people in the business have experienced this more than once. While on hold, conditions in the wind have to be monitored. A dominant condition must be determined. Dominant condition is simply that condition that prevails most of the time.
Then we look for variations in the conditions. The best way to do this and any other wind analysis is by looking at mirage through a spotting scope.
Mirage is simply heat waves reflecting from an object. The warmer the day the more mirage you will see. Anyone who has watched a fire has noticed the distortion that develops from the heat. This distortion is what we look for in the scope. When these waves are observed, movement will be identified. The direction of that movement is the way the wind is blowing at that specific place, at that specific time.
Mirage is best captured by focusing on the object you are reading and then turning the scope slightly out of focus. Your ability to see the distortion will improve. You're looking for movement in the heat waves themselves. Watch the waves bend, to see the affects of the wind and read the wind direction.
The best place to read mirage is where you can. Ideally you want to be halfway between you and your target directly in the path the bullet will travel. However, ideal is not what is always available. You may have to improvise, at a different distance, look for a sand box, automobile, pavement, window sills, basically anything that is in the sunlight.
Watch the waves and observe the changes. Remember that wind is rarely constant. This brings up a critical point. When you dope the wind, you have to shoot the wind. Don't dope for a ten mile an hour wind and then wait for a lull in the breeze to shoot. Guess what? You are going to miss. You must be observant to change and change with the conditions. A marksman who stays in position for an extended period will change sight settings several times. It is not uncommon for competitive shooters, at six hundred yards, to make adjustments four or five times in a twenty minute string of fire.
If the mirage is moving vertically, it is called boiling. This is an indication the wind is moving very slowly or is non-existent. Many people think that this is the time to deliver a shot, it isn't.
This vertical distortion makes the target elongate, appearing higher than it is. This perception increases at greater distances. Most competitive shooters will not launch a round in this condition and to them there is only an X-ring at stake. I would say if competition shooters shy away from this shot it certainly warrants our consideration.
Another thing to consider about a boiling mirage is this. If you look at your target and see right to left or left to right movement but can't really decern wind direction, turn your scope right or left until you see a boiling mirage. That will be the direction the wind is blowing. Watching the mirage move from right to left or left to right is what the marksman is looking for when doping for windage. Generally, when we consider doping for wind, it has to do with moving the bullet from off center, to center.
The slant of the mirage's waves will provide information about velocity as well as direction. The greater the slant the faster the wind.
When you see the lines of the mirage horizontal and straight you have a really good wind, usually twenty plus miles per hour. This is an extremely poor condition to deliver a shot in.
Also keep in mind that when you have this type of wind, even of lesser velocity, the target will be distorted in the direction the wind is moving. The target will be left, or right, of where you think it is. Example
If you have a bright, sunny, day and distortion surrounds your target, watch the mirage.
You will see it elongate the target. If the wind is blowing from left to right you will see the right side of the target get bigger. This area of the target will appear to swell in the direction the mirage is moving. If the swelling of the area appears to pulsate, that means the wind is intermittent. Again, these effects increase with distance.