High scope and canting - the end of an ancient myth

Discussion in 'General Airgun Chat' started by maestro, Mar 9, 2012.

  1. maestro

    maestro European Champion 2018

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    INTRODUCTION

    I've heard many times from old shooters that 'the high scope isn't good because it's much more sensitive to canting' – does it sound familiar? It seems to be logical at first glance – but not anymore when one investigates it a bit more thoroughly.

    I started to deal with this topic back in 2007 when I was shooting with a 6 ft-lb rifle and used a rather high scope (we used to shoot up to 50 metres even with the low-powered rifles). I was told then that 'oh boy, you're gonna suck with this high mount and miss even with the slightest cant, because high scopes are more sensitive to canting errors, all riflemen advise to set the scope as low as you can.'

    ...

    The whole article can be read in my blog:
    http://www.szottesfold.co.uk/2012/03/high-scope-and-canting-end-of-ancient.html

    ...

    This is the final result of the test, see the shots merged on one drawing. It speaks for itself.

    [​IMG]

    My conclusion is that the scope height has NO effect on canting error so watch the bubble my dear friends even with the lowest scope because it's equally important with any scope height.
     
    Last edited: Mar 12, 2012
  2. maestro

    maestro European Champion 2018

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    ...

    CONCLUSIONS

    1. In general, especially in FT shooting, where we do the required correction of LOS within our scope (i.e. adjusting turrets or holding over with certain mildots), the canting error is totally independent from the scope height, higher scopes are NOT more sensitive to canting angle than low ones.

    2. If we do the correction outside the scope (i.e. we have zeroed the rifle at a given distance and then shoot at another target with a holdover which is measured at the target), the canting error can be different – more or less – with the higher scopes. It will be more if the new range is greater than the zero range and less if it's shorter.

    Considering that we are allowed to use bubble levels on our rifles so canting is not a real aspect for us, I say that we can rise the scope as high as we want to, it will mean no disadvantages with canting. The more important point is that even those who have lower scopes have to pay the same attention to levelling the rifle because their canting error is the same as the others' with high scopes.
     
    Last edited: Mar 12, 2012
  3. AIRFIX GILLY

    AIRFIX GILLY WFTA World Champion 2012

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    Genius??

    Is Andras a mathematical genius?? Having looked at the dater he`s just posted I think so!:)
    Andras, I am too currently working on a project of my own in applied mathematics and maybe you can add the final answer as I`m struggling:confused: I`ve consulted my professor but he`s stuck.:eek:
    I`m working on what the probability is on Marc fisher missing a target. My equation so far is:-

    V=785 ft per sec
    F=4.67% per sec
    m=8.44 grain pellet
    W=4.77m per second
    X= human error
    Y= size of kill
    Z= distance from target


    V x m (w - f)2 x Z3 x Z to the power 4 divided by 8.44 + Y (40mm) X X to the power 5 = ??? help ???

    what do you think??:confused:
     
  4. Charlts

    Charlts Getting dusty

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    I liked the pictures of you shooting from your car! But the maths went over my head.:)
     
  5. Tench

    Tench WHFTA World Champion 2016.

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    Awsome!!:eek: i didnt think there was anyone that clever in clackers!!!:D
     
  6. TOOL

    TOOL Independent FT Pumper

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    Gilly my Tin Chicken Guru !

    I am absolutlly fu%$ed with the mathematical question !

    It would take a pure genius to work it out !

    Warm regards with a sprinkle of Moon Dust

    Tool
     
  7. Jamesy

    Jamesy Weerach ninja

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    Tis easy.. yes, he will miss a target.;)
     
  8. ellis d

    ellis d Active Member

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    The only project uve been working on, is how long does it take u to blow up your rubber dwarf doll, shouldnt take to long, i would have thought, shes only small.. but prob looks big to u...:D:D
     
  9. Conor

    Conor Never been banned from sales Staff Member

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    Here is a question for you,
    If you have a high scope and mis range (under range) a long target (55 yrd) by a yrd or so, but because you have the scope high you have only a few clicks between 50 and 55 it makes little difference but you cant the gun.
    Same scenario on on a low mounted scope with lots of clicks between 50 and 55yrds, which is worse??
    You suggest cant in this instance is not as big an issue for lower scopes if I read correctly, surely the higher scope might just give the chance if slipping into the kill zone (low) whilst the low scope has no chance even with the wind perfectly judged.
     
  10. Neil

    Neil MFTA Winter League Champion 2011 and winner of som

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    My conclusion is " I don't give a **** "

    If I keep hitting more targets than anyone else, guess what, they give me the trophy!
     
  11. maestro

    maestro European Champion 2018

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    Conor, if you shoot at 50 m with an average FT-rifle which is zeroed at 49 m (say misranged and set to 49) you will shoot low with 5.9 mm (5 cm high scope) or 4.9 mm (10 cm high scope). But the pellet drop is 280 mm so there will be not too much difference between the canting error circles, every 1 ° canting means 4.8 mm offset for both cases. This is negligible, compared to the many inches which we have to give for the wind.

    Strictly theoretically, when you misranged, shooting low reduces canting error and shooting high increases the error. Since the amount of increase/decrease is less with a higher scope, if you under ranged then the lower scope is better and if over ranged then the higher one.

    "Theoretically, there's no difference between theory and practice. But practically..." :D
     
  12. Dave Ramshead

    Dave Ramshead England HFT Team squatter

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    A good read again Andras, it's great to see maths & physics (plus a heap of effort) beat myth & bulls***:D
     
  13. nemesis

    nemesis 55yrd standing expert, or was it 8 or 9?

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    I was once shooting with a cant at the redferns winter league,it was in the lane next to me.
     
    Last edited: Mar 9, 2012
  14. ellis d

    ellis d Active Member

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    Are u sure u weren't looking at a reflection:D:D
     
  15. nemesis

    nemesis 55yrd standing expert, or was it 8 or 9?

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    Dont think so coz this one had a big gob on it to match its head.
     
  16. ellis d

    ellis d Active Member

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    Has the nice person got a name ? :eek:
     
  17. Tone

    Tone Active Member

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    Nice work Maestro, its good to know the result and conclusion although I did nots spend too much time on the Maths, can you do an equation ref lubing pellets and whether it makes a difference?:D
     
  18. Gibbs

    Gibbs New Member

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    Excellent work there Andras!
    The only thing I can add is that with a higher scope your FT outfit has a higher centre of gravity and is therefore more likely to be canted than a more balanced and lower CoG setup.

    Atb,

    Alec.
     
  19. airborn68

    airborn68 Member

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    Great post thank's.

    It certainly made my night shift go a little quicker

    Jon
     
  20. maestro

    maestro European Champion 2018

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    You're totally right, Neil, this all is only scratching the surface instead of the Real Knowledge while we all do know that:

    "The real cant problem is if you want to hit a target but you can't..." :)
     

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