Rechambering a .308 Win barrel to .300 Win Mag.

5pins

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Dec 9, 2006
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Charles Town, WV
Anyone cut a .300 Win Mag chamber into an existing .308 Win chamber? I have a new Shilen short chambered barrel, but I need a .300 Win Mag barrel. I don’t see any reason it can’t be done, but I have never done it before.
 

FisherT&C

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    yes you can do it. I've converted some old 1903's to 300 Win Mag. A 308 should be no problem.
     
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    5pins

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    Dec 9, 2006
    79
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    Charles Town, WV
    Make sure your 308 barrel has a twist rate you can live with when throwing heavy/long bullets.

    ./
    It's a 1 in 10. Right now I'm using a 1 in 9, and it shoots the 220gr Sierra MK very well, but I can go lighter if need be.

    Going to need to verify contour is safe.
    I think it's the standard varmint, so it should be fine.

    I also have a used, about 20 round, Shilen chambered in .308 Win with a 1 in 8 twist, but it's a straight contour.
     
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    MJC

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    I also have a used, about 20 round, Shilen chambered in .308 Win with a 1 in 8 twist, but it's a straight contour.
    According to Sierra, the 1:8 twist is right for their 230's.
     
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