375 RUM Barrel Selection help

Discussion in 'Gunsmithing' started by trout-n-salmon, Aug 2, 2011.

  1. trout-n-salmon

    trout-n-salmon Well-Known Member

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    I am building a 375 RUM to shoot the Barnes 350 TSX &/or the Matchking 350. I intend to have the barrel length 26" from recoil lug to crown + muzzle brake. What would you all recommend for number of grooves and twist rate to optimize the 350 grain bullet?

    Thanks for the assist.
     
  2. Dano1

    Dano1 Well-Known Member

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    I personally would get a Krieger #6 contour 4 groove 1-12" twist bbl. This will stabilize either one of those bullets.

    I have one in a .30-06 AI and it's amazing. I have a Shilen Select match in a 6.5-06 AI and I wish it was a Krieger.

    Dan
     

  3. J E Custom

    J E Custom Well-Known Member

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    I would look for 6 to 8 groves.

    The grooves are only 3 to 5 thousandths deep and the larger bullets are hard to get started rotating
    and will sometimes shear the jacket unless there are plenty of groves and lands.

    I have had the best luck with 8 groove barrels with 10 to 14 twist the 1 in 12 should be good for
    the 375 rum because of velocity. the old 375 H&H did ok with the 1 in 10 (Slower).

    For the 416s the 1 in 14 seems to be the best.

    Barrel length will be ok (26") + the brake.

    J E CUSTOM
     
  4. trout-n-salmon

    trout-n-salmon Well-Known Member

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    Thanks for the information gents. I found a twist rate calculator online as well and it is recommending 1/14" for a 350 grain going 2600 fps.
     
  5. 338 bruce

    338 bruce Well-Known Member

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    I used a 1-10 twist in my 375 tejas (375 rum imp) and it works very well with the 350 smk and the 260 accubond. My barrel is 31" and my velocity is 3005 fps with the smk.
     
  6. trout-n-salmon

    trout-n-salmon Well-Known Member

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    That is smoking for a 350 grain bullet. What is your group size with the 350 SMK at 3000+ FPS. What barrel maker chambers in the 375 Tejas? Where did you get the reloading dies?
     
  7. 338 bruce

    338 bruce Well-Known Member

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    3/4" at 100 yds, brad star ogdon utah