Cooper 92 6.5-284 gaining accuracy

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by smoked, Nov 22, 2017.

  1. smoked

    smoked Well-Known Member

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    I am messing with a new cooper 92 in a 6.5-284. Two different loads. 143 eldx with 57.5gr retumbo and benchrest primer with lapua brass. 2960 fps best group after ladder test was .740. Second load is berger hunting vld 140 same everything except 58gr retumbo 3030 fps. best group .639.

    57 rounds down the tube and the groups are not even close to the test target that came with the rifle. Also Berger says coal of 3.228. I am jamming lands at 3.15 and cant physically chamber one at book length. Not sure what book coal is for the eldx

    Kinda mad right now as I could have done that with a 700 dollar remington or a 300 dollar salvage.
    scope is a nightforce shv 5-20-56 moar.

    Brass has only been fl sized

    Any ideas?
     
  2. L.Sherm

    L.Sherm Well-Known Member

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    Call Cooper ask what powder and bullet they are probably using a reamer that doesn't have the freebore for 140 class bullets
     
  3. adam32

    adam32 Well-Known Member

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    A .639 group out of a 6lb rifle isn't bad at all...I'd venture to guess it's shooter error as much as rifle.

    Lightweight guns are much harder to shoot itty bitty groups.
     
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  4. smoked

    smoked Well-Known Member

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    Your right. I have never shot until today.
     
  5. Mikecr

    Mikecr Well-Known Member

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    You seem concerned about a book COAL..
    What COAL tested best in YOUR gun?
     
  6. smoked

    smoked Well-Known Member

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    So far 3.10. Long ways out from Saami specs. The thought of being out that far leads me to think the rifle was not set up properly before leaving the shop.I am going to load some from 3.05 to 3.10 and see what happens. This isnt the only 6.5 I been messing with. A savage lrh out of the box shoots bugholes. Wish I could say the same for my cooper.
     
  7. L.Sherm

    L.Sherm Well-Known Member

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    You say properly, I'm not saying that the freebore has anything to do with the groups your expecting. Did you state to Cooper what bullets you were intending to shoot? The 2 biggest questions people should ask are what reamer are you using I.E freebore and what is the neck dia.I.E. no turn or not.
     
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  8. smoked

    smoked Well-Known Member

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    Just loaded 120 gr gmx with rl 15,17,25, imr 4350 and 4831, Heading to the range. Wll report back. Also retumbo 140vld hunting from 3.05-3.10 in .01 increments. And 143 eldx with retumbo 3.110-3.150
     
  9. solobigdog

    solobigdog Member

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    just call Cooper with the serial # of your rifle and they will give you their test load,i've done this with my 3 Coopers and they flat shoot
     
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  10. Mikecr

    Mikecr Well-Known Member

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    With a Cooper, I'm sure that with full seating testing (Berger's recommended), and full load development, you can get below 1/2moa.
    I don't know what kind of accuracy should be expected from such an overbore cartridge..
     
  11. WeiserBucks

    WeiserBucks Well-Known Member

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    You should expect outstanding accuracy from a 6.5x284 , easily one of the most accurate rounds available , with many records set and many championships won with it .
     
  12. smoked

    smoked Well-Known Member

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    Interesting results.
    gmx 3 shot all 3.10 length just diff powders
    rl-15-1.046
    rl-17-2.066
    rl-25-1.156
    imr4350-1.616
    imr4831-1.016

    Interesting thing is they all had two close and one flyer
    2 shot gmx without flyer
    rl-15-.036
    rl-17-.886
    rl-25-.276
    imr4350-.386
    imr4831-.686

    Berger 3 shot all same charge retumbo, diff seat
    3.09-1.76-pulled this one
    3.08-.776
    3.055-.836

    Berger 2 shot no flyer
    3.09-.656
    3.08-.356
    3.055-.486

    ELDX 143 GR 3 shot lenght vs group retumbo
    3.110-1.226
    3.115-1.556

    ELDX no fly length vs group
    3.110-.926
    3.115-.876.


    looks like I need to go to a five shot group and figure out this flyer
     
  13. WeiserBucks

    WeiserBucks Well-Known Member

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    Could the barrel be touching the stock somewhere? Loose action screw possibly ? Sounds like you are well on your way, just gotta figure out the fliers.
     
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  14. hydehunter

    hydehunter Well-Known Member

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    my model 21 6.5-284 shoots 143 eldx-47.0 Rl22 ans 210m primers into .350 groups,140 Noler Bt 46.0 Rl22 210m into .211 groups and berger 130 hunting 50.0 Retumbo (very hot) 210m into .443 groups ( going to drop down to 49.0 and see what happens) all loads done at 3.0 to 3.1 oal hope this helps.Jim