Reading the wind

[N Jensen]

Being mostly a NRA XC shooter and long range, everything I learned about reading wind was on my own, nothing came from a military school of marksmanship. In the AF, just about 98% maybe higher qualify at 25 yds with a M-16. So what I did learn came from shooting with either the Marine Corps or Army shooter during rifle matches that I went to on my own. Once I obtained more skills, I took what I learned and learned even more on my own. But in the end, it's about putting the bullet in the center. All the very good shooters on a rifle range or match would be happy to explain what they used to determine what windage to use.

In HP the target requires a very good rifle, good ammo, a shooter who can hold elevation and being able to read the wind.

General rules I follow and pass on to others.

- Majority of the time making any adjustment in windage will result in a better score than doing nothing.

- The wind in the first 100yds has more effect on the drift of the bullet than wind down range

- Wind has pick ups and let ups, one must know the bracket of windage required lowest amount and highest amount required before shooting.

- A fishtail wind is the hardest wind to shoot in.

- Just because it's calm doesn't mean wind won't change later on, cause it will.

- Using a electronic wind meter is not the best tool to use, might even be the worst tool.

- A wind calculator based on your bullet and velocity is a must to have or memorize it.

- Mirage is indicator of speed and angle to relationship to the target.

- Always compare the velocity of the mirage in the scope to the velocity before firing the next shot, it will determine if adding or subtracting windage for the next shot.

- The faster you shoot the less windage changes you need to make.

- Chasing the spotter is worst thing to do (Adjusting the windage based on where the bullet hit the target and not on what the wind is doing)

- Everyone will eventually be caught with a wind change while aiming the rifle, but if ones plays a strategy and stages the shot up wind during a wind build up will result in more ten ring shots than doing nothing.

- Finally, knowing the speed and angle of the wind to the target, is a must before firing the first shot.

Simple tricks to determine angle of the wind to the target: Kick or throw some fine dirt in the air or even a handful of grass, look at the wind flag. But the most accurate is using your spotting scope. Focus on the target and back off on the focus to a point half way down range. If the wind is from the right, turn the scope left and watch the mirage moving right to left in the field of view. As you move the scope to the left you will notice the mirage to run slower and slower until it comes to a boil. That is the true angle of the wind to the target.

Next is speed of the wind. Watching flags is a start, many range books has mph vs angle of the flag. Mirage which is slow moving and wavy in the scope is 3 to 8 mph, flat mirage moves very quickly is 15 to 20 MPH, Mirage in between is variable as the mirage flattens out, the wind is 10 to 15 mph. But you get the idea, slow moving mirage lots of waves is a slow and flat out mirage is MPH is fast. Out on the web is more about mirage and speed of the wind, USA Palma team has some good info available I believe.

Put the two together and using a wind calculator/diagram will give you windage correction based on angle and velocity. The Marine Corps competition Rifleman's data book has a very good diagram from 200 yds to 1,000yds based on the 172 g bullet.

As you watch the wind before it's your turn to shoot will help, the wind has let ups and pick ups. Record the velocity of the highs and lows you observed. As you shoot the first shot, this will help you determine where to start for windage before firing that first shot.

In HP at 600yds to 1,000yds is also known as string shooting. One fires 2 sighters and 20 shots for record all in a row, or string. As you shoot the wind changes, the more the wind changes the more windage adjustment is required.

To help myself determine a correction in the wind, I remember what the velocity of the mirage was before I fire the shot and look at it again after the shot is fired. Is the wind velocity the same? If so and I guessed the wind correctly I have an X on target. Before I fire the next shot, I again compare the mirage velocity to what it was after the previous shot. Is it the same or not? If the mirage is moving quicker, one needs to add windage. Remember, I said to pre record the estimated lowest windage and estimated highest amount of windage needed. If the range was 3 1/2 mins to 7 Min's, the windage was at 4 1/2 mins for the x-ring shot.

This where experience comes in, just how much an increase relates to the correction needed. But doing nothing is worse than doing something, so adding a minute of wind to 5 1/2 would be a good choice. Was the mirage equal to the fastest observed during prep time? If so put on 7 mins of wind and shoot. Knowing the variables, watching the mirage pick up and slow down will help you determine what to do next.

These basic questions of what was the mirage doing before, after and before the next shot and where the shot was on target will help you determine to take windage off or put it on.

The basic strategy in HP is shoot quickly and reduce the amount of windage adj needed during the 20 shot string. I normally shoot 20 rounds in 12 minutes, the guy who takes 18 minutes has to make more changes.

The ten ring at 600 yds is 2 MOA. If the wind is building up set the windage to hit the target on the wind side of the target, Doing this will allow while aiming the rifle a cushion if the wind continuous to build pushing the bullet into the center of the target. Once the wind has max out in velocity and mirage observed in the scope, then park the bullet on the downward side of the ten ring and let the wind drop off and move the bullet back into the center.

That is a lot of info, can't type any more. I can add more latter if questions are asked.

Edited February 2, 2014 by N Jensen

[planeflyer21]

That's some great info brother N Jensen!

 

Wind is something that takes practice…no matter how much instruction you have been given.

[Tripledeuce]

    Thanks!  Thats very helpfull to us that don;t have access to longer ranges to pracitce.

   Respectfully

   Terry

[washguy]

Thank You ! that will help my 500 yd shooting a bunch :) Wash

[Libertarian623]

Mr Jensen, thanks for putting that on paper. I find that there are times when you hear something a hundred times and for what ever reason it never clicks in your head . And then there are times when someone explains the same thing a different way and it clicks . Well in reading your post a lot clicked for me. Thank You.

[MONTANA308]

Thank you for the info. nice wright up!

[N Jensen]

Curious how many of you in competitions and what distance, HP, F-class. Curious I'm.