Which groove is best?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by crowsnest2002, Apr 29, 2012.

  1. crowsnest2002

    crowsnest2002 Well-Known Member

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    Joined:
    Sep 13, 2009
    I was cruising around on Pacnor's website looking at what they had available. What are the major differences in grooves per barrel. I know most barrels are 6 groove, but what would be the major benefits of using a 3 groove system. The only thing I can determine is it would reduce the rifling print on the bullet which would decrease the drag it creates while spinning through the air. What are the restrictions of a 3 groove 1-8 twist if any? Just hoping to pick your brains. Thanks in advance.

    Barry

    6mm (.243")3 groove
    7"
    8"
    9"
    10"
    11"
    12"
    13.25"
    14"​
    4 groove
    7.50"
    8"
    8.60"
    13.75"
    14"​
    5 groove
    5"
    6"
    7"
    9"
    12"
    13"
    15"
    16"​
    6 groove
    9"
    10"
    Polygonal
    8"
    9"
    10"​
     
  2. FEENIX

    FEENIX Well-Known Member

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    Dec 20, 2008
    Last edited: Apr 29, 2012

  3. Bart B

    Bart B Well-Known Member

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    Dec 25, 2005
    With 30 caliber barrels used in competition, 5- and 6-grooved ones typically shoot 160 to 220 grain bullets most accurate. 4-groove ones are favored for 145 to 155 grains. And either 3- or 4-groove ones do wonders with the 135-grain bullets used in benchrest matches. And there will be a few exceptions.

    I don't know about smaller calibers, but my guess is they're much the same