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Re-Chambering?

jmdvet
What are my caliber choices with a 300 win mag action? Having never re-chambered a rifle before, I'm supossing that I have the gunsmith re-barrel the action? That said, what are my choices with a rifle currenly chambered in 300 win mag? Could go down to a 7mm 08 for example? 338-06?
Thanks.
jd
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Comments

10 comments

Date Votes
  • Wehrmacht_45
    What kind of action is it? You would most likely have some issues because the mags would be too long. If the mag is internal a new follower and spring with a spacer might be used.
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  • Hawk Carse
    Your bolt face is correct for any of the belted magnums. It might work with some of the large head diameter unbelted magnums, I don't know which. It is not right for a standard head diameter related to .30-06 or .308.
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  • jmdvet
    Thanks for the feedback. The action is weatherby mark v. How large can I go on belted magnums? e.g. 338-378? 378? (sticking with weatherby calibers)
    thanks
    jd
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  • MIKE WISKEY
    "(sticking with weatherby calibers)"......without altering the bolt face the largest 'Weatherby cal. you can rebarrel to is .375 Weatherby. that said if you want a 'big thumper' some others to consider would be .416 rem. mag., .458 lott (check mag. lenght on this one), .375 rem ultra mag.
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  • mrbruce
    The 460 Weatherby has the same boltface as the 375 Weatherby and is the largest in that lineup... The 416 Rem Mag has a smaller bolt face by .050.....
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  • nononsense
    jmdvet,

    You can re-chamber your existing barrel to a cartridge that is dimensionally larger than the current .300 Win. Mag. The new chamber needs to clean up the existing chamber.

    You can also re-bore the existing barrel in order to use larger caliber bullets such as 8mm, .338, .358, .375 just as examples and not a comprehensive list.

    You could have the bolt face opened up to accept the larger cases with the .582" rims but bear in mind that this will entail changing out the magazine box, follower and having the feed rails and feed ramp adjusted by a gunsmith.

    You could conversely, have the bolt sleeved or bushed down to take the smaller rim cartridges (.473") such as those made on the '06 case. In this instance though, you will encounter some difficult changes in the area of feeding geometry.

    Your best bet is to consult some of the cartridge drawings to see which ones fit in the existing parameters and those that are larger that might be made to fit with alterations.

    Best.
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  • MIKE WISKEY
    "The 460 Weatherby has the same boltface as the 375 Weatherby".......I'm certainly no expert on the weatherby cals. but isn't the .375 weatherby based on the .300 case necked up (as opposed to the 378 weatherby based on the .460 case)
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  • nononsense
    MIKE WISKEY,

    The .375 Weatherby is a modification of the .300 Weatherby case which has the .532" rim diameter.

    The .378 Weatherby has a .582" rim diameter.

    Best.
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  • MIKE WISKEY
    thanks non, that's what I said the first time[8D]
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  • nononsense
    MIKE WISKEY,

    Just makin' sure someone had your back with the numbers.

    Best.
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