.308 barrel lenght?

Discussion in 'Gunsmithing' started by tfosters01, Mar 2, 2011.

  1. tfosters01

    tfosters01 Active Member

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    I am thinking of building a .308 bolt action rifle and am most likely going with a 1/10 twist 26" bull barrel. Weight is not an issue. Can I gain any accuracy or any other benifits if I was to get the barrel in 28" or 30" instead?
     
  2. J E Custom

    J E Custom Well-Known Member

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    1 in 10 is a good twist rate for most bullets over 160 grains.

    The barrel size is your call But I would recommend something like a palma contour around 28"

    You dont gain much over 28" and the rifle will be muzzle heavy.

    I like the Sendero contour or a #8 Lilja contour in 30 cal.

    The true "Bull" Barrel is a straight cylinder and serves no purpose in a longer barrel.

    Just a recommendation.

    J E CUSTOM
     

  3. tfosters01

    tfosters01 Active Member

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    Thank you, very useful information.
     
  4. ltrshooter

    ltrshooter Active Member

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    I have studied this myself because I had a Sendero that shot well but the long barrel wold bang into deer stands and was a little tough to shoot off hand. What the experts seem to say is you gain velocity with the longer barrel and not much else. My 20 inch LTR loses about a hundred feet per second compared to the longer Sendero I sold. What I gained is a rifle that is a little more accurate and a lot easier to handle. The shorter barrels are more rigid and I think that helps in the accuracy department. My Sendero would shoot FGMM 168's great but every other commercial ammo would open up. For example the combined technology bullets would go into 1 1/2 on the Sendero and all three holes are touching on the LTR. In fact the first three commercial ammo tested all grouped with the holes touching! I was wary of letting the Sendero go as it has grouped under 3 inches at 500 yards but only with Federal Premium. Boy was I tickled when I first shot the LTR. I would still like to have a longer barreled 308 for long distance shooting because to get the 100 fps I lost because of barrel length, I have to shoot 150's in the LTR and they will probably not prove to be as accurate. I got some Berger VLD's and a quick load set up to barrel time the test load but have not done so yet. I realllly enjoyed my Sendero but I love my LTR!
     
  5. ltrshooter

    ltrshooter Active Member

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    In reading my reply, I don't think I really addressed your question. I would think that you would not really gain much velocity or accuracy in going with longer than 26 inches on a 308.
     
  6. trebark

    trebark Well-Known Member

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    Once again, J E Custom is wise AND beat me to the reply!
     
  7. tfosters01

    tfosters01 Active Member

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    Great information again. Thanks!
     
  8. backwoods83

    backwoods83 Well-Known Member

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    I'm not a gun smith or genius but for most palma classes, F-class, or tactical 308s use a 12 twist and some a 13. Most consider the 155-175grn bullet class and I doubt very seriously you will gain anything by using anything more than a 24" 12 twist NBRSA heavy varmint contour. Once again, just my 2 cents.
     
  9. Trickymissfit

    Trickymissfit Well-Known Member

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    one inch strait contour in 1:9 twist @ 23" length
    gary
     
  10. trebark

    trebark Well-Known Member

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    9 twist? 1:10 would be sufficient. Even a 1:11 will stabilize 208Amax and 210VLD.
     
  11. BigSkyGP

    BigSkyGP Well-Known Member

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    5r, 5C, 6, 4, or 3 land/groove?
     
  12. tfosters01

    tfosters01 Active Member

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    I'm not sure about how many lands the barrel has, it's a Savage 12 LRPV. If I plan to get serious about this I should know these things.
     
  13. Trickymissfit

    Trickymissfit Well-Known Member

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    just had my best luck with the faster twist with slower velocity rounds in 30 caliber. I know it sounds strange, but has always worked well for me. Then when you look at the .308 trying to push a 190 grain Sierra at 2450fps; it's gonna need every bit of help it can get. By the way the Hornaday manual uses 1:10 twist barrels for their Service Rifle section with bullets upto 178 grain. Of course they also use a 1:12 twist for the generic stuff in .308. In the Speer manual, they use a 1:10 twist barrel, but also make note that Winchester liked to use 1:12 twist barrels. I don't own a .308 anymore (it was a 1:9.5 twist), but own several 30-06's. A couple use 1:12 twist barrels, and groups start to open up at 175 grains. I have one that has a 1:9 twist barrel, and it will shoot anything well once I find the sweet spot. I also own one with a 1:10 twist barrel, and it's similar to the 1:9 but have never shot anything heavier than 190 grains thru it.

    But alas if 1:12 twist does well in a .308 for you, then have at it. (note: the spec for a Palma twist is 1:13 @155 grains) If you wanta have some fun, try a 1:17 twist with lightweight bullets (<120 gr.)
    gary
     
  14. Coyboy

    Coyboy Well-Known Member

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    But alas if 1:12 twist does well in a .308 for you, then have at it. (note: the spec for a Palma twist is 1:13 @155 grains) If you wanta have some fun, try a 1:17 twist with lightweight bullets (<120 gr.)
    gary


    I'll second the 17 twist, I have a 26" light palma contour that I shoot 110 v-max bullets at 3450 fps. It's a hoot and with a mini muscle brake it kicks like a 22 hornet.
    From 100 yard zero to 400 yards it has less than 20" of drop.
    It's like a 22-250 on steroids.