Does my zero change with a power change on a variable scope?

Discussion in 'Scopes, Optics, LRFs, Spotters, BoreScopes' started by chkunz, Oct 20, 2019.

  1. Ned Ludd

    Ned Ludd Gold $$ Contributor

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    Power, not powder...as in the scope magnification setting, not the little dark kernels that go inside the cartridge. ;)
     
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  2. Straightshooter1

    Straightshooter1 Gold $$ Contributor

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    Yup. You're right.

    Funny how I read that more than once at the time and still read it wrong.:eek: I'd make poor proof reader. :(
     
  3. Ned Ludd

    Ned Ludd Gold $$ Contributor

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    Don't feel bad. After reading your post, I had to re-read the original three or four times just to be sure it didn't actually say "powder". LOL.
     
  4. ILya

    ILya

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    In a FFP scope, by design, the POA does not change with magnification. You can have apparent change if your eyepiece and sidefocus are not setup correctly: as the exit pupil gets larger you can induce and error, but if everything is set up correctly the POA should remain dead on.

    With SFP scopes, POA can and usually does change with magnification, but with high quality scopes it is such a small change that you can not measure it without specialized instrumentation. Naturally, my earlier comments about eyepiece and sidefocus adjustments apply here as well.

    The only variable SFP scope where POA can not change with magnification, to th ebest of my knowledge, is March's EP Zoom.

    ILya
    www.darklordofoptics.com
     
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  5. Hermantk

    Hermantk Silver $$ Contributor

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    Higher MV can result on a lower POI at very short distances but a higher POI at longer distances. A change of 15fps in MV will result in about a 5" elevation difference at 1000 yards. Not a big deal at all when hunting but a very big deal in competition.
     

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