I've said it before and I'll say it again,

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by goodgrouper, Sep 25, 2007.

  1. goodgrouper

    goodgrouper Well-Known Member

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    CASE DESIGN IS EVERYTHING!

    I just finished working on a standard 6mm br with an 8" twist in a Krieger 4 groove barrel that is 26" long. I have also had a hand in or worked directly in load development on 4 6mm br improved's with like barrels and twists to the standard 6 br mentioned above. And from the data I have collected I can say one thing with absolute confidence.....the 40 degree shoulder on the improved version burns powder better period. ANd not just one kind of powder but all powders tried.

    In the total amount of loads tried in the 4 improved's which numbers somewhere around 80 loads, there have been SEVEN loads that didn't produce standard deviations in the single digits! That is freaking amazing.

    On the standard 6 br shooting exactly the same bullets and even the same lots of powder, it has had exactly 47% of it's loads produce standard deviations in the single digits. Of the loads that didn't produce single digits, 25, 30 and even higher SD's were found. The improved's seven loadsthat were not single digit were ALL under 20.

    The proof is in the pudding here. That 40 degree shoulder vs the 30 degree shoulder is night and day when shooting heavy bullets with appropriate powders. Oh, and not to mention, the improved version shoots the bullet 100 fps faster on average with less powder on average too!

    Now before someone jumps all over me for this comparison not being fair, let me just say this. I know that it was just one 6 br standard barrel being tested. But it was 4 improved 6 br's being tested-not just one. ANd of the four, they said the same thing. This case is efficient, is easy to load for, goes fast comparitively, and accuracy is top notch. The standard 6br is a good cartridge too but just not as good as the improved version for doing load development.
     
  2. NYLES

    NYLES Well-Known Member

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    GG will it hit the dime? No matter what anyone says IT WORKS for YOU!
     
  3. BountyHunter

    BountyHunter Writers Guild

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    Go Dasher and BRDX!!!!

    My BRDX puts them in there.

    BH
     
  4. wildcat

    wildcat Well-Known Member

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    GG, this is some good stuff, very interesting. I decided to build a 6BR. I am currently going with the standard neck 6BR, however, I am thinking about going to the improved version.

    Wildcat
     
  5. Flybuster

    Flybuster Well-Known Member

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    That's nice to hear. I have in plan a 6 Dasher. I too plan to use the Krieger 4-groove .236 land cofiguration. I think I buy bulk 107 grain matchkings, hey if they work for Richard Schatz to shoot a .888" at 600 world record...I think they will work good for F-class.

    It just seems like the neatest little case, being so accurate and all.
     
  6. James H

    James H Well-Known Member

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    I'm not trying to be contrary but as NYLES said what about accuracy. Low ES is great but better aggs. trump it.
    James
     
  7. goodgrouper

    goodgrouper Well-Known Member

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    Better aggs trump ES but at long range I don't see getting good results without low ES. But no need to worry, both of these cartridges get both very easily.
     
  8. NYLES

    NYLES Well-Known Member

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    GG you know Im messin with ya but will it hit the dime? You know if you were to put that dime over the X, I think youd do much much better....

    Is this the gun you shot that killer group with?