Objective sizes

Discussion in 'Long Range Scopes and Other Optics' started by DUKFVR, Jun 16, 2010.

  1. DUKFVR

    DUKFVR Well-Known Member

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    Looking at going with a Leupold VX-3 4.5 X14 LR with the B&C reticle. Is the 50 MM obj worth the xtra money & weight added to the scope over the 40 MM? I haven't bought a new scope in awhile ,so is the VX-3 difference between the older VX-III really discernable? I'm leaning to the 40MM this time. Any help would be appreciated.
     
  2. japple

    japple Well-Known Member

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    If you are going to do alot of shooting at over 10x magnification then I would reccomend you go with 50mm. If you plan to stay under that then the 40mm will be great! It all has to do with light transmission to your eye! you really want to keep a ratio of 4:1 (objective lens:magnification) 5:1 is better. Keepin that first number higher is going to allow alot more light through the lens and your vision through the scope will be much clearer!
     

  3. muleyman

    muleyman Well-Known Member

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    I believe that most if not all Leupold LR scopes are 30mm main tubes so I think for this one the 50mm would be a better choice, especially at the prime times of the hunts.........
     
  4. Jamie6.5

    Jamie6.5 Well-Known Member

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    Weight and light aren't the deciding factor between 40s and 50s for me.
    With my stock(s) it's cheek weld.

    I hate it when one change causes me to make 2 or 3 others to make the first one work.
     
  5. japple

    japple Well-Known Member

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    Jaime,

    That is a very interesting point. I never thought about cheek weld when he posed that question. I was thinking of it from a purely optical perspective. But the point you raised could cause some serious accuracy problems if you have to change your cheek weld (atleast until you get used to it).
     
  6. bigngreen

    bigngreen Well-Known Member

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    Once I went 50mm objective with a 30mm tube there is no going back to the smaller stuff!! I'll make what ever adjustments it takes to shoot the larger scopes now.:D
     
  7. DUKFVR

    DUKFVR Well-Known Member

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    I have been using a 3.5x10x50mm Leu. I am going to upgrade my scope. I haven't had any problems with that set up ,but did start looking into the cheek weld as I read more on here. I do know that I have to pick my head up off of the stock to see thru the 50mm. Tried a 40mm on my sons gun & didn't have to get up as much. I guess it would boil down to what feels best. I'm learning more as I go here & read post from others ,so trying to get what works best for my shooting. The furthest I would shoot game at this time would be 300-400 yrds. I guess It would be best if I put some kind of cheek piece on the stock if I want to go 50MM again. I really Appreciate all the help everyone is giving.
     
  8. trebark

    trebark Well-Known Member

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    previous posts have hit the big points...

    50mm helps with light transmission and exit pupil size.

    If the 50mm changes your cheek weld, just get a cheek piece and that will resolve it.