COAL for 300 weatherby?

Discussion in 'Reloading' started by lsm62, Sep 16, 2011.

  1. lsm62

    lsm62 Well-Known Member

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    Sep 9, 2010
    just wondering what people are running their COAL at.

    i am going to have a barrel made and was going to use a standard over all length (3.56) and set the refiling back to .005 off the lans with a 208 Amax. I now am thinking of using an overall length of 3.6 and setting off the lans .010.

    other specs, heavy palma barrel 26 in long with a 1:10 twist on a mark v action.

    any thoughts or suggestions would be appreciated.

    Thanks lsm
     
    Last edited: Sep 16, 2011
  2. MagnumManiac

    MagnumManiac Well-Known Member

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    If you build this rifle to do what you're saying, then it will give you dangerously high pressures with factory rounds!
    All Weatherby chambers have 'freebore' built into them which effectively reduces starting pressure and allows higher velocities than normal due to heavier charges of powder that are used.

    With most bullets, an OAL of 3.560" will give a freebore of around .500", I know mine did. The freebore on average is close to .500" on most Weatherby rounds.
    There is no point trying to load rounds to be close to the rifling in such a rifle barrel, in fact it can reduce the accuracy of the rifle. The long bullet jump gives the bullet time to straighten before it engages the rifling fully!
    Weatherby chamberings are very accurate, and even moreso with well tuned ammunition tailored to each rifle. One of the smallest recorded groups @ 1000yrds was shot from a 300Weatherby rifle!

    I would leave the chamber as is from factory.

    Cheers.
    gun)
     
  3. dig

    dig Well-Known Member

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    I am shooting a 300 Wby with the 190 Berger HVLD at 3.575 COAL. This works in the mag and has given me best accuracy in the 27 inch Shilen tube. There is defiantly "free bore" and for some reason this rifle does not like the overly hot loads but I will sacrifice 100 fbps for .45 inch five round groups. h4831sc has been the most consistent powder although not best velocity.
     
  4. backwoods83

    backwoods83 Well-Known Member

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    My custom 300 wby "short throat" only has .060" freebore (definently will not work with factory ammo, period) I push 208 amax's .008" in the lands and the OAL is still 3.806" which puts the boattail right at the neck/shoulder junction, these are extremely accurate setups but the downfall is not being able to use factory ammo, if you get in a bind.
     
  5. Hornhunter32

    Hornhunter32 Well-Known Member

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    I also load the 190 VLD. What rifle do you have? How many grains of H4831sc are you using for the 190 VLD?
     
  6. dig

    dig Well-Known Member

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    It's a Remington action, shilen tube 27 inches, McMillan Stock. The gun like's the lighter loads currently with the 190 BVLD, using 77.5 Grns of h4831sc, NORMA brass, CCI Mag primer, moving at 2940 at 1,150 ft 90 degrees. I have pushed it faster but loads open up.
     
  7. backwoods83

    backwoods83 Well-Known Member

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    You may want to try 3.625" if it fits and use about 82.5grns H4831 or the same 77.5grns but Imr4350 and use a fed210m or cci br2 primer, cause your 300+ fps behind what that thing is capable of with a 190.
     
  8. dig

    dig Well-Known Member

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    Thanks I have tried the COAL at 3.63. I shot 165 grn Sirraccos prior at blazing speed but the rifle just doesnt like the fast loads with the Bergers.