7mm-300 winmag

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by hogslayer, Aug 16, 2009.

  1. hogslayer

    hogslayer Member

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    I am in the process of a new build chambered in a high performance 7mm round. I would like to know if any of you out there have any real world experience with this cartridge, I will be shooting 162 grn amax for varmints and 180 grain berger for big game. I believe that I could achieve 7stw velocitys with less powder and also be able to seat the vlds out to the lands and still fit in the magazine.
     
  2. Michael Eichele

    Michael Eichele Well-Known Member

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    The 300 winnie and the 7mm Rem mag cases are VERY close in design. It is alot of headache and expense to go with a wild cat that offers such little performance gains IF any over a readily available cartridge. If you want a 7mm wild cat, dont joke around. Use a bigger case.
     

  3. Limbic

    Limbic Well-Known Member

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    My seven mag will pust 180g Bergers at 2950-2970fps. It works for me because the bullet specturm is what I need. It is hard to increase velocity without increasing powder or using harder brass.

    I'd get the STW.
     
  4. LRHWAL

    LRHWAL Well-Known Member

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    You may search for the .280 or .284 Jarrett (or 7mm Jarrett?) - I think that was basically what he designed using the 300 WM case. He claimed it was very efficient as I recall.
     
  5. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

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    Michael E is right on the money with his advice. Why not just get a 7mm STW and outperform what you will go through quite a bit of trouble to build. I have shot the 7mm-300 wby and the now named 7mm STW since the mid 70's and they are great 7mm's that will outperform what you are looking at. The 7mm-300 ultramags I did just went through barrels to quick but were very good long rangers with heavy bullets such as the 200 grain Wildcat and 180 Bergers. I decided from a lot of testing the 7mm-300 wby and the 7STW were about the best it got in 7mm before barrel wear got to be to much of a factor.
     
  6. distantfoe

    distantfoe Well-Known Member

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    Up until the loss of 300win Lapua and RWS brass, I had considered a wildcat similar to this. Check out this write-up on the 284 jarrett, pretty much dups stw velocities with less powder. With the strong brass it could of been something.

    http://www.jarrettrifles.com/calibers.html
     
  7. LRHWAL

    LRHWAL Well-Known Member

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    Distantfoe,

    I thought RWS Brass was still available in 300 WM. I do see Huntingtons no longer stocks them. Is that the end of it?

    WL
     
  8. grit

    grit Well-Known Member

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    7mm Dakota
     
  9. AZShooter

    AZShooter Well-Known Member

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    You could neck down the 375 Ruger to 7 mm. Dave Kiff said that he had many requests for that reamer when the 375 Ruger first came out. It would be similar to the 7 Dakota with lower brass costs.

    FYI I have a 30" 7 rem mag that gets 3100 fps with the 180 Berger VLDs. 69 grs of RL-25.
     
  10. Nomosendero

    Nomosendero Well-Known Member

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    I read the Jarrett info & if it is true, it is very impressive. They say it is very close if not duplicates the STW, I would think that with the 180 Berger or heavier & slowest powders the STW would pull away, but maybe I'm wrong. Does anyone know the case cap of the 375 Ruger case & how it compares to the 300WM?
     
  11. AJ Peacock

    AJ Peacock Well-Known Member

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    According to Quickload, the 375 Ruger holds 99gr of water, the 300WM holds 88-95.5 depending on brass. Quickload lists 300WM (W), 300WM (N), 300WM (R), 300WM (F), 300WM (@). It shows 300WM (N) as 95.5 and 300WM(R) as 88, the other are in between.

    AJ
     
  12. Nomosendero

    Nomosendero Well-Known Member

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    Thanks!