FFP long rang scope

Discussion in 'Long Range Scopes and Other Optics' started by Gurnz, Jul 8, 2011.

  1. Gurnz

    Gurnz Member

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    What is the purpose of the front focal plane on a long range scope? Is it necessary or just nice to have and how does it help. I assume it has to do with your reticle and it's correlation to the target when adjusting power on your scope. Thanks for the info
     
  2. SBruce

    SBruce Well-Known Member

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    With FFP, the reticle doesn't appear to change size (in relation to the target image) when we change the power setting. This is a benefit when we use the reticle to hold over, hold off for wind, or call shots, or attempt to range or calculate size with the reticle. All these things can still be done with the scope on any power with a FFP scope.

    2nd FP scopes need to be set on a specific power for the reticle to subtend the given amount. If we change powers, the reticle size (again in relation to the target image) changes too. Not necessarily a bad thing in some cases, because if we've got a 1 moa scope reticle and it feels too cluttered, we can dial down the power and make the spacing increase to 2 moa (just an example). Another benefit of 2nd FP, if we use hold over technique; we can adjust the power to where certain marks on the reticle match our drops at a certain distance. This is something that can't be done with FFP.

    FFP = When target appears larger (as we increase the power), reticle appears larger too. Visa Versa if we decrease power.

    2nd FP = as target appears larger, reticle stays the same size, thereby appearing to decrease in size relative to target.

    Hope that helps.
     

  3. Artful

    Artful New Member

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    Jul 8, 2011
    Good summary - let me just say that trying to set a variable to some power in the middle of it's range and have the distance between the dots meet the same specifications each time is not as easy as they would have you think.

    For example say you have a 6x24 scope but it must be at 10 power to have the distance between two points be 24 inches - if you have no stop and each time guess the 10X setting and then try and use the dots to measure a known 24 inches you will find that less than half the time will you be able to get it to be a true measurement.

    At least that's my experience with SFP and Mil-dot ranging.:rolleyes:
     
  4. RFtinkerer

    RFtinkerer Well-Known Member

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    Jun 7, 2011
    The SFP Vortex Viper 6-24 I have has detents at 24, 12, 8, and 6 powers showing 1x, 2x, 3x, and 4x multipliers. I kind of like it. I also have the FFP on the other rifle, and I honestly don't know which I prefer.