How do you compensate for mirage?

Discussion in 'Long Range Hunting & Shooting' started by benchracer, Nov 17, 2012.

  1. benchracer

    benchracer Well-Known Member

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    A little more than a month ago, I was able to shoot one of my rifles @ 600 yards for the first time. I was shooting in a stiff, gusty crosswind. The rifle I was using was chambered in 6.5x55, shooting 140g Berger VLD's, and had a Nikon Buckmasters 6-18x40 w/side parallax adjustment and mil-dot reticle.

    It wasn't difficult to get dialed in for the distance. I was surprised how easy it was to get dialed in for the wind. Once dialed in, my first two sighters on an F-Class target went into the ten ring. I was able to bust clay targets on the berm with ease. I was shooting fist sized five shot groups that showed very little vertical dispersion...

    Then the sun came out... My target began to shimmer and dance... And mirage began to give me fits. My fist sized groups became watermelon sized groups with a lot of vertical. My ten ring shots became seven ring shots. In short, the mirage kicked my newby butt.

    I have read a lot on this site about compensating for trajectory, wind, up/down angle, etc. However, I have seen very little information on how to deal with mirage.

    One thing that occurred to me after I left the range that day was that I should have turned the power down on my scope. I think that might have helped.

    Still, I wonder: Is it possible to dope mirage? If so, how does one read and then dope mirage? If not, what can I do to mitigate its effects?

    Is mirage commonly encountered in LRH situations?

    I would sure appreciate some advice from some of you seasoned long range hunters...

    "You're doin great, killer! The champ ain't laid a glove on ya." "Well keep your eye on the ref, cuz somebody's kickin' my ass!"
     
  2. 4xforfun

    4xforfun Well-Known Member

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    I have a hell of a time with mirage.....mirage is VOO-DOO. That being said, it can also help you read the conditions. I know from my 1000 BR experiance..when you go from zero mirage to mirage....you will start hitting high....your sight picture rised due to the mirage. Wind reading....I also know you can watch the flow of the mirage to judge wind speed...the more sideways the flow, the faster the wind.

    I try and pay atention to the mirage, but I spend most of my time watching the flags. BUT..there are no flags in the field!!

    One trick that works for helping read mirage/wind. Dial you paralex in a ways...focus on the mirage CLOSER to you and watch the flow of the mirage. Keep dialing around and watch the mirage at differnt yardages.

    Again...MIRAGE IS VOODOO!!!!
     

  3. benchracer

    benchracer Well-Known Member

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    Thank you, 4xforfun, for sharing your 1000 yd BR experience with me.

    For field shooting purposes, your advice to use the mirage to read wind conditions makes a lot of sense.

    When it comes to actually compensating for mirage, though, it sounds like kind of a crapshoot. I am thinking that the only way to learn to deal with it is to practice a lot in mirage in order to develop a more refined "best guess" kind of firing solution.

    Your comment about mirage causing you to shoot high seems to be pretty consistent with what I experienced on my last range trip. I will keep that in mind next time around. I am curious to see what will happen if I back the power down and hold slightly low (or dial a couple clicks lower).

    One question I have is if wind can affect the perceived location of a target in mirage conditions. For instance, without wind, we already know that mirage will cause the target to appear to be located higher than it actually is, causing the shooter to miss high.

    If there is a crosswind, say from left to right, would the wind cause the mirage to make the target appear further to the right than it actually is, as well? It occurs to me that such a condition could cause the shooter to think that a bad wind call was made, when the real problem involves compensating for the image shift caused by combined wind and mirage.

    As you said, "VOODOO!" Maybe I should just keep a witch doctor on speed dial instead...

    "...I called the witch doctor. He told me what to say. He said ooh e ooh ahh ahh ting tang walla walla bing bang..."

    Maybe that would help me as much as anything else I might try!
     
    Last edited: Nov 21, 2012
  4. 4xforfun

    4xforfun Well-Known Member

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    As far as the left right thing..you are correct....but...how much of that movement is wind, and how much of that is mirage?

    As far as turning your power down, don't bother. The mirage is still there, you just cant see it as well at a lower power. If you can't see it, you can't read it!!

    Good luck,
    Tod
     
  5. RMulhern

    RMulhern Well-Known Member

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    Swag!!
     
  6. rdsii64

    rdsii64 Well-Known Member

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    The best way to compensate for it is to learn to read it. dial your scope back until you get a usable sight picture, then use the mirage to help you read the wind.