first focal plane and second

Discussion in 'Long Range Scopes and Other Optics' started by boattaileddeth, Apr 7, 2009.

  1. boattaileddeth

    boattaileddeth Member

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    ok new to this site but not that new to shooting.

    Correct me if i'm wrong but with a FFP the reticle does not move with magnification, thus point of aim point of impact bam. On a SFP if you increase the mag your point of aim point of impact should move correct? if so then how much?

    Application is hunting 300-600 using a NF NXS 3.5-15x56 NPR-1
    Going to use 6.5 grendel AWS 24" barrel 120gr Nosler BT

    any light shed on the FFP and SFP movement of the reticle would be much appreciated
     
  2. RockZ

    RockZ Well-Known Member

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    For your 3.5-15 NPR1 : assuming that the lines on the reticle are 1moa:

    With the FFP reticle the values of the reticle lines remain the same at any power, since the size of the reticle changes with magnification. So no matter what power you have on your NPR1 each line is 1moa.

    If you have a SFP then the reticle size does not change with magnificaton, only the target size changes . For this reason, the lines on the reticle are only 1 moa at 15x and would be 2 moa at 7.5x. The value of the lines are inversely proportional to the power on the 2nd FP scopes.
     
    Last edited: Apr 8, 2009

  3. MAX100

    MAX100 Member

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    FFP scope the reticle and picture gets larger on higher magnification and they get smaller on lower power. Not the best setup for very accurate shots. Great for sniper tactical shooting matches where you do a lot of ranging, magnification changes and holdovers. They are faster and require a few less steps in math calculations.

    SFP scopes the reticle stays the same no matter what power you are on. POI doesn't change with magnification changes on quality scopes, only on cheap scopes. Great for paper punching and hunting. If you know your equipment well they can be just as fast as a FFP scope in tactical shooting matches.


    GC
     
  4. jwp475

    jwp475 Well-Known Member

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    First off the point of aim and point of impact should not change with either a FFP or a SFP scope as the power is changed.

    I dissagree with the comment that a FFP scope is not good for presicse shooting at long range, as I have both styles ( S&B and Nightforce) and I have no problems with either at very long range. The Reticule substions are calibrated on all powers with a FFP scope, but are only calibrated at one power in a SFP scope. Either one will serve you well.
     
  5. MAX100

    MAX100 Member

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    FFP scopes some reticles get so small @ lower power that they can be lost in the background. Also the reticle gets larger on higher magnification and can cover a small target making it harder for a precise shots.

    This is the very reason why many prefer thinner finer reticles on a SFP scopes for long range shooting.

    There are draw backs to both FFP and SFP scopes but I prefer the later for the reasons I mentioned.

    Here is Falcon Menace 4-14x44mm FFP Tactical Rifle Scope on 14X. You can imagine how large it would be on higher power @ longer ranges on a small target.

    [​IMG]


    Here is the same reticle on 4X


    [​IMG]




    GC
     
  6. jwp475

    jwp475 Well-Known Member

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    Perhaps you have never looked through a S&B with a P-4 fine reticule, it is not to thick at high power and yes it does get small at low power I have no problem seeing the intersection even with my 58 years old eyes. Blanket statements are rarely accurate across the board
     
    Last edited: Apr 8, 2009
  7. RockyMtnMT

    RockyMtnMT Official LRH Sponsor

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    You can use your drop chart/hold overs on any power with a ffp. You can not do this with sfp. I doubt that you will use the scope on it's lowest power at long range, but if you do, the sfp scope will probably cover the target with the reticle so you can't tell where you are aiming unless you run the power up to make the target larger in proportion to the reticle. The ffp reticle will stay the same relative size on the target at every power.

    Jmo, the ffp is much more usable in every situation. There is a reason it costs more and people who know, buy them.:)

    Steve
     
  8. boattaileddeth

    boattaileddeth Member

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    Alright cool, so for the application, 6.5 grendel which is a really flat shooting round anyway, the FFP sounds like it would do justice. thank you all!
     
  9. LewisH

    LewisH Well-Known Member

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    BTE, as the other guys have explained, it's really very simple: in order to use a drop chart and the reticle marks (mil dots of moa marks) directly, without further calculations, you must crank the power setting to a specified power on the SFP scope (like 15X on the NXS 3.5-15).

    But with the FFP scope, the marks apply at ANY power setting.

    I finally got this thru my thick skull; and yes, if I could afford one, I would opt for the FFP scope. :cool:
     
  10. boattaileddeth

    boattaileddeth Member

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    I totally get it now, needed to do some extra drilling for my head. lol. FFP is the way for me simply because the deer or elk is not going to wait for you to pull out your ballistic calculator PDA, or be there long enough for you to do mental math in your head. I don't know about anyone else but things need to be simple in the heat of the moment.
    I'm in Iraq right now, all i have is time and money saved up, d amn right i'm going to pay for a FFP Scope. hahahaha:D thanks all again! Much appreciated! I'm really humbled by all the knowledgable people here. thanks
     
  11. NoBambi

    NoBambi Member

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