longer barrel slower powder????

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by mcharger440, Dec 28, 2012.

  1. mcharger440

    mcharger440 Well-Known Member

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    I am asking based purely on theory but would going from a 26" barrel to a 31" barrel alter your load if so how (338 ultra mag) using retumbo and Berger elite hunter 300gr I haven't even got it Bach from my smith yet im just looking for knowledge help if you can
     
  2. Greyfox

    Greyfox Well-Known Member

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    In my experience, changing to a slower burning powder with a longer barrel is not a mandatory consideration. It's an option that could be considered to refine a load. Of more importance is the effect of the new barrel in terms of accuracy, velocity, and ES. Using your current load in the new 31" barrel will likely produce a higher velocity, and require a change in your ballistic information. I have more often found that switching from a long barrel to a short one may require changing to a faster powder because of the blast produced by not having enough barrel length to burn all the powder. For me, the best situation when changing to a different length barrel is when I get the same, or better accuracy and ES, and only have to modify my ballistic information any change in velocity. This all assumes the previous barrel was a good performer and being changed because I burned it out. If the barrel was changed because of poor performance, I would consider a slower burning powder in my load development with a replacement barrel that had the length to burn it.
     

  3. mcharger440

    mcharger440 Well-Known Member

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    thank you that's what I was after one more question on the same note my Col has been pushed out to 4.088 so I loaded 95gr of retumbo and am not close to capasity so I have a lot of room am I on the right track with powder or should I contemplate a slower powder and more of it to fill the space as much as possible I know this is just theory as I haven't even pulled the trigger yet just want to know my thinking is right or wrong
    p.s. Ackley imp. On the 338 ultra or not worth the effort?
     
  4. Greyfox

    Greyfox Well-Known Member

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    Retumbo is a pretty slow powder. If you have room in your case, I would work up slowly, or you could consider a faster power that fills more of the case. I happen to prefer the temperature stability of Retumbo. Improving the 338 Ultra? I am happy with the ballistics of my 338 Lapua, so I'm the wrong person to answer this.
     
  5. mcharger440

    mcharger440 Well-Known Member

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    I was going to build a lapua but my smith didn't like the idea in a 700 and the 700 was already an ultra mag so it was alot cheaper not to mention I traded a 300 weatherby vangaurd strait for it