Custom Build - Barrel Throats for 7mm 140 grain bullets

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Jerry D, Mar 10, 2009.

  1. Jerry D

    Jerry D Active Member

    Messages:
    37
    Joined:
    Dec 28, 2008
    So I'm posting again, slowly taking advice and deciding on components and specs for my rifle... it is my first rifle so I'm taking things easy and asking lots of questions as I want it to be PERFECT!! :)

    Anyhow its going to be a 7mm-08 for use up to 500 yards max on deer/antelope etc... Normal shots will be probably 200 or less but I'm going to take it out farther on paper and if the time comes around when I need to take one, I'll be able to.

    My plan is to use 140 grain hunting bullets in a 1 in 9.5" twist with a 20" barrel. Bullet selection will be 140 grain accubonds/partitions/tsx...

    Do I need to specify a throat dimension? How does one measure throat dimensions required for specific bullets? I understand its the distance from the tip of the chambered brass to the where the rifling starts - basically the portion of the barrel where the bullet sticks out.

    Also do I need to specify any type of special chamber for a 7mm08 or is it standard. I assume there are no variations like there are in some bench rest chambers due to different brass being used.
     

  2. Coyboy

    Coyboy Well-Known Member

    Messages:
    2,132
    Joined:
    Jan 30, 2005
    Jerry, reamers can be made anywhere within sammi spec, with different length leads and neck dia. It really depends on what your after as far as user friendly.

    I would load a dummie round to the length that you would like it and send it to your smith. If you want tighter tolerances ask for a match reamer with a no turn neck, throated for your dummies oal. This will get you a nice fit.

    It might be to tight if you run in dusty sandy locations and don't keep your rifle clean.