THE "COMA ABERRATION" AND HOW IT EFFECTS YOUR RIFLE SCOPE

Discussion in 'Long Range Scopes and Other Optics' started by WWB, Sep 5, 2019.


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  1. WWB

    WWB OFFICIAL LRH SPONSOR

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    Perhaps it would be worth your while to get this information from the horses mouth. For further information regarding this matter, "please," contact the General Director of NASA, or Dr. Walter Peshke, (former chief scientist for Ziess/Hensoldt) or perhaps Dr. Hesse, (former physicist of Schmidt & Bender) who will be able to help you out. That is IF you really want to know.

    For additional information, please visit my YouTube Channel at https://www.youtube.com/channel/UCjrt0xWHJOAZlrIw1jSHiyA?view_as=subscriber
     
    Last edited: Sep 9, 2019
  2. idcwby

    idcwby Well-Known Member

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    I was really hoping this would turn into a good discussion and hopefully learn something. Instead it turned into a ....... and now no one may be able to learn anything.

    idcwby
     
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  3. PredatorSlayer

    PredatorSlayer Well-Known Member

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    Why aren’t anybody’s responses showing up? Looks like they were deleted? I can only see them when the OP responds to comments. This train must have gone off the tracks?
     
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  4. milo-2

    milo-2 Well-Known Member

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    I am still trying to figure out if this is an advertisement for a shooting school or a solid point of information, and I am being sincere.
    I am not sure if there is a prs style match today that does not have a holdover stage and guys do quite well on them. Granted, they may not be high incline shots, which itself presents issues, like were you shooting the correct range.
    We practice hold overs-hold offs enough to know hitting 10" plate to 1K is not that difficult, as wind skews most of the missed shots. The farther you get away from the center aiming point of the scope, especially with a ballistic reticle, your aimpoint resolution becomes less defined. And with a FFP reticle, after 6 mils or 20 moa below the dot or crosshair, now you have to turn the power down making your sight picture even less desirable.
    Far from saying the op is wrong, the scope-lines in the vid are self explanatory and may be something each of us need to experiment with on our own, I know I will. I know from range shooting holdovers, not many targets at various ranges line up with the exact line needed for pinpoint accuracy. But I can move steel around to match that up.

    I will agree totally though, if I want to increase my chances of a hit, I will be dialing elevation, and if the wind hold is beyond a certain point, either 1 mil or 2 moa, I am going to have some windage dialed also to tighten my sight picture. That is my comfort zone.
     
  5. lancetkenyon

    lancetkenyon Well-Known Member

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    Wow. This turned from a heated debate/discussion into a monologue with no differing opinions. That sucks. Not sure WHY, but IF it was at the OP's request, it would have been better to nuke the whole thread rather than just delete opposing opinions. If it was a mods doing, I still stand by my statement to just nuke the whole thread. Is this 1984....
     
  6. WWB

    WWB OFFICIAL LRH SPONSOR

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    Why do people chose to listen to novices who do not possess the scientific background? Why do they choose them instead of the PhD's? The PhD's that wrote the software that put spacecraft on Mercury? PhD's that develop the military grade, and weaponized lasers. PhD's that are the geniuses
    Lance,
    If you have any questions, please feel free to contact me. More videos to follow.
     
    Last edited: Sep 10, 2019
  7. WWB

    WWB OFFICIAL LRH SPONSOR

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    milo-2, Now that you have dialed in your scope using the holdover method of aiming, specifically for shooting flat, have you shot on angles at distances past 600? And yes, it is without a doubt, solid information while attempting to push the MSC to civilians/hunters.
     
    Last edited: Sep 10, 2019
  8. milo-2

    milo-2 Well-Known Member

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    First, I said we practice it, no where close to being mastered. I fail to understand if the range is indeed verified, and the dope is verified to hit, whether incline or flat land, how or where the difference would be on incline shooting.
    Also in the original vid, the lines not matching up represent less than 1/10 of a mil, that equates to less than 3.6 inches at 1K. Now I agree that the 3.6" of error at 1K is not something in the grand picture that need be there, considering all else in a hunting situation. But at 600, that now becomes even less significant at 2.1". Guys free recoil off crappy rests resulting in more error than a tenth mil.
    I will say again though, if it was I using the goofy reticle in OP vid, I would dial and make the shot before I counted then recounted, then shot. So I agree, you have came this far, why chance it.
    Scopes have came a long way just in the last 3 yrs compared to what was available, advancements in most areas, etched reticles, etc...
     
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  9. WWB

    WWB OFFICIAL LRH SPONSOR

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    Finally... A legitimate, non harassing response. I LIKE IT. THANK YOU.
    1. The scope in the picture appears to be at an angle of incidence that will reduce the amount of effects from Snell's.
    2. Think about the sun moving throughout the day. This is what causes the "wondering zero."
    3. Shooting flat produces minimum effect which presents itself when moving your eye to outside 1/3 of the optical center of the lens and into the curvature of the lens.
    4. Increase the magnification, and you increase the distortion.
    5. Shoot up or down on angles, and the angle of the lens has a much greater angle of incidence in relation to the sun than when shooting flat. Did you have a chance to look at the second video that I uploaded? The one that describes the effect(s) of Snell's Law? If not, you can view it from here.



    6. The Increase angle of incidence (angle of the lens in relation to the sun) when aiming on angles, greatly/greatly increases the refracted light coming through the scope. It's like putting a stick in a pool of water. The stick bends downwards and away from the light source. The deeper that the stick goes into the water, the more distorted / bent it becomes. Lenses in your scope, whether it was from the courts of Baghdad in the year 900 or today are designed to focus a "contained" amount of light (photons) which move through the center of the scopes lens. When it reaches the ocular lens, the ocular lens focuses a beam of light onto your pupil, matching it. This is why your eye relief must be near perfect. Move the light source and you, the Shooter, must correct for it.
    7. When the light rays approach the scopes lenses on an angle, the light rays are bent downwards (refracted) and away from the light source, just like the second video I post in this thread, and similar to the stick in the pool of water analogy. This produces an image that is/is distorted, although you do not notice the distortion.
    8. It is imperative that a Shooter maintains a Data book and notes everything. This is where the Shooter will learn and understand how their Rifle trends and how it shoots in different climatic environments and circumstances.

    This topic can continue, however, it becomes very time consuming and is why it is not included in my video. My video has two purposes; to educate without giving away too much information that a student would learn in my class, (although they need to experience it for themselvs), and also to promote the MSC.
     
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  10. Bstick

    Bstick Well-Known Member

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    Without watching the YouTube video and reading through all the other stuff that was deleted, are you telling me that hold overs aren’t accurate and I shouldn’t be holding over?
     
  11. WWB

    WWB OFFICIAL LRH SPONSOR

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    Let me tell you a true story. I was working with Two Lead Instructors from the Marine Corps. In fact, one ran the Sniper program. I picked a target that was at 930 meters (1,017 yards) on a 25 degrees incline. Their data was 8.2 mils of elevation. When they held over utilizing a gridded reticle on the 8.2 mil mark, both of them missed 1.6 mils high, (59"), and approximately 1.3 mils to the right.
    When they dialed 8.2 mils onto their scope, they both hit center mass. They went back and forth with this exercise until they finally accepted it.
    Prior to coming out, they had been able to "true" or "Force" AB and the holdover method of aiming to work by cheating the Real/True drag curve, matching the point of impact with their point of aim. (IF the software works in the first place, why would you have to fudge it?) However, this was accomplished on a flat square range, and in one meteorological environment. Once they moved to a different altitude or the met data changed, all of their data changed too. Since this exercise, their practices have changed. This wasn't the only group of Snipers that I trained who discovered that both/both the hold over method of aiming and AB was a travesty. Now, there will be people who have made it work for them in one environment, however, I Guarantee you, that when you move to a different AO or shoot on angles, it will not/not be accurate by any means. BTW, watch the videos.
     
  12. Bstick

    Bstick Well-Known Member

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    well it’s 8.3 mils to a 1000 in my 6.5x47 at 0 degrees. It’s 7.3 mils at a -25 degree inclination per AB.

    Are you telling me that if I hold 7.3 mils I will miss and if I dial 7.3 I will hit?
     
  13. WWB

    WWB OFFICIAL LRH SPONSOR

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    YES ABSOLUTELY. TRY IT FOR YOURSELF. Holdover and you will miss high
    Also, as I mentioned earlier, IF you take five Kestrels with AB on them, or any other device, make each units setting identical, then make an identical new gun file on each unit, and input the exact same problem to solve; i.e 900 meters, 25 degrees decline and a 5 mph wind from 9 O'Clock, all five units will produce five different solutions. Try that too... Then, turn on the Coriolis routine and solve the same solution again. It will be different than your first solution.
     
    Last edited: Sep 10, 2019
  14. Bstick

    Bstick Well-Known Member

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    And how much higher will I miss