throating 338 Lapua for 300 Berger

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by rscott5028, Aug 26, 2012.

  1. rscott5028

    rscott5028 Well-Known Member

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    I ran across a great deal on a new Savage 110ba 338 Lapua barrel and couldn't resist.

    So, I built a rifle and test fired yesterday. Everything is just about perfect.

    However.... 300 Bergers at the lands (3.689") are just about book COAL (3.681") and I can't help but fret over the fact that these bullets take up a lot of case capacity.

    As this is a single shot only and I will only ever shoot long/heavy bullets, I'm thinking of throating this barrel for the 300's.

    Just eyeballing it, looks like maybe 10-15 grains of H1000 worth of wasted space.

    For those shooting 338LM, what COAL are you running and do you feel the lost case capacity of seating to mag/book length vs seating the base of the bullet just inside the neck is a material issue for ELR?

    It would also be nice if someone with Quickload or other relevant experience might shed some light on the expected pressure/velocity trade-offs here.

    Thanks!!
    Richard
     
  2. rscott5028

    rscott5028 Well-Known Member

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    Well, my eyeballing isn't that great... so, I measured about .211" worth of bullet shank wasted space.

    If my math is right, that's about 1.24 ml. ...not sure how many grains that works out to.

    Also, the barrel is only about 25 1/2" without the brake.

    -- richard
     
    Last edited: Aug 26, 2012

  3. ZSteinle

    ZSteinle Well-Known Member

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    quickload says 338 lapua mag with a 300 smk seated to 3.681 oal and volume of case occubied by bullet is 16.1 grain. Take it to 4" oal and volume occubied by bullet drops to 9 grains. But keeping pressure the same 60,000 psi you gain around 40fps by going to 4" oal. So not much.
     
  4. rscott5028

    rscott5028 Well-Known Member

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    Well, that hardly seems worth the effort unless there's some other advantage to be gained.

    thanks!