Mk 4 6.5-20 Vs 8.5-25?

Discussion in 'Long Range Hunting & Shooting' started by EXPRESS, Jul 11, 2012.

  1. EXPRESS

    EXPRESS Well-Known Member

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    I am tossing up between the 6.5-20x and 8.5-25x but before the long string of people chime in saying that 6.5-20 is plenty, I prefer higher magnification. It makes me feel more precise.

    What I want to find out about the eventual differences in the scopes has more to do with their clarity in marginal conditions.

    For example on one rifle I have a NF 8-32x and I find that as with ll scopes, on the highest setting you get diminishing returns. However, on a 32x scope, when you set it at 20x, or 25x, you tend to get better clarity, less distortion and a greater FOV than you would with a scope that maxes out at the same 20x.

    In fact I don't often use the 8-32 on 32x, but tend to use it around the 25 mark quite often, just by looking through it and turning up the magnification until it starts suffer, then back down.

    Can I assume with these two Leupolds that the FOV should be pretty much identical at 20x and 8.5x?

    Will the 8.5-25 give me better resolution at 20 than the 6.5-20, or is this just an impression I have?

    One more consideration is that with a front focal plane reticle; the higher magnification will impose a reticle that appears to be and in the case of the TMR I have chosen, that will allow you to see more through the gap in the middle of the junction of the crosshairs, so I wonder if that will be distracting or take away from the more precise feel I get from a fine second plane reticle at high magnification?
     
  2. J E Custom

    J E Custom Well-Known Member

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    Thats a tough question so I will answer based on My experiences with both scopes.

    If I were going to shoot F-Class I would chose the 8.5x25 (I assume that they are both have
    50mm objective lens). the head position is more critical on the higher powder but this can be
    dealt with when position shooting. I find little if any difference in the light gathering ability
    of ether scope on max power (There probably is because of the additional power of the 8.5x25)
    but I never have both scopes together at the same time.

    The 8.5x25 should improve the group size because of the extra power but at long range it
    may be a detriment because of mirage, position and heart beat will all be magnified.

    The 6.5x20 is better for hunting where the distance and position is unknown because it will go
    down to 6.5 and if a running shot presents it's self it is easier to acquire the target with it.

    I actually prefer hunting with a 3.5x14x52 for it's all round usability.

    On the front focal plain issue I am still undecided on what is best for my use. so I will pass
    an opinion on it for a while.

    Just my opinion.

    J E CUSTOM
     

  3. Outlaw6.0

    Outlaw6.0 Well-Known Member

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    I have owned & used both the 8.5-25x50 SFP TMR & 6.5-20x50 FFP TMR. I haven't had any issues with the "gap" in the FFP TMR being a problem however, it's farily new to me. I haven't noticed a huge difference in clarity or resolution between the two (both MK 4's) but there is a difference in tube diameter, the SFP MK4 was a 30mm, my FFP MK4 is a 34mm tube. The 6.5-20 is going to offer more elevation adjustment when the tube diameter is the same.


    The first picture is of my 34mm FFP TMR @ 1060yds on a 16" (ish) target. PS-taking pics through the scope can be dern tough!

    The second picture is a reticle pic of a FFP TMR.
     

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  4. yotehunter243

    yotehunter243 Well-Known Member

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    What power setting is the picture taken on?
     
  5. Outlaw6.0

    Outlaw6.0 Well-Known Member

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    Good question... I really don't remember! Should have been 20x, but does not look like it... I know. Probably just a result of my poor photography skills.:D
     
  6. barnesuser28

    barnesuser28 Well-Known Member

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    I have a 6.5x20 Mark 4 on a 338 Lapua and at 20X on a STOP sign at 991 yards the gap in the middle is the size of the inside of the P.
     
  7. EXPRESS

    EXPRESS Well-Known Member

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    Wow. I haven't posted on here for a while and some time ago I tried an Italian LR forum that I abandoned very quickly after seeing the kind of people, attitudes and competence on there.
    We really are lucky to have this community of shooters here.

    Here I have got real world, relevant and contextualized info in the space of a few hours on a fairly specific question. Thanks very much for the input!

    Keep it coming...
     
  8. Greyfox

    Greyfox Well-Known Member

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    I have used both and prefer the 6.5x20 for hunting. While I use the 25x for competition, I have found the difference between 20x and 25x when hunting to be slight, if noticable at all when shooting big game and coyotes. My bigger issue is the 8.5x low end. For low light, off hand, or heavy brush, which is always a possibility when hunting I find 8.5 too much power and a disadvantage. Also, the 25x Mark 4 has a very noticeable difference in eye relief change over the power range. I think this is a design flaw of the 8.5x25 M4. It's just me, but I personally don't think the FFP option is worth the extra $$$$ for hunting purposes.
     
  9. WildRose

    WildRose Well-Known Member

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    I have both, love both, and see no real advantage to the 25x over the 20x other than magnification. Of course the higher the magnification is dialed up the more light required to give you a good image.

    I like the higher power for really judging racks but other than that out to 1,000yds there's really no need for more than 20x.

    As for the reticles I have both the TMR and Mil dot and very much like them both. I'd suggest trying to borrow a scope with the TMR reticle and shooting it some before deciding as for some people it's just "too much clutter" but I really like it particularly for spotting misses and making precise adjustments on the fly without having to dial. Just see the spot of the impact on the grid and place that spot on target for your follow up shot and it's a done deal.