7mm Rem Mag ammo through a 7mm Wby Mag

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Big_Tex22, Jul 30, 2011.

  1. Big_Tex22

    Big_Tex22 Active Member

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    Had this post over in guns for sale forum also, got some good replies, thought I'd put it here to get a few more views.

    Looking at a Weatherby Mk V Deluxe in 7mm Wby. Thing is, it has had 7mm Rem Mag ammo fired in it, I doubt very much at all as it has been rarely fired by its current owner.

    I can understand the confusion on the ammo the way Weatherby stamped these barrels, and the owner let me take the rifle to shoot and gave me a few boxes of 7mm Rem mag that he had had.

    So I scratched my head over it and called weatherby with the number and yes it is a wby mag.

    My question is should it be okay to shoot the weatherby ammo through it after having fired rem mag ammo? Spent RM cases fireformed nicely to the wby dimensions, no pressure signs or abnormalities.

    I really like this rifle and plan to buy it from him even if it constitutes a new barrel job.
     
  2. Edd

    Edd Well-Known Member

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    Have you chambered any of the Remington ammo in that rifle? I'd think it would be difficult to close the bolt. I don't think there will be any damage to the rifle.
     
  3. Big_Tex22

    Big_Tex22 Active Member

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    The bolt will close on the rem ammo, with a slight resistance. Just from visual it seems that the only difference is the Remington Magnum has a little longer shoulder than the Wby mag which causes the little bit of chamber tightness.
    The Rem Mag is has a shorter neck though.
     
  4. Edd

    Edd Well-Known Member

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    Those are the two differences. The cases I have used for several years in my 7mm Remington started life as 7mm Weatherby cases.
     
  5. backwoods83

    backwoods83 Well-Known Member

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    It is perfectly fine, I have seen this in the past mostly with the vanguards and people putting 300wm ammo in a 300wby. It fire forms the cases doesn't hurt anything but typically isn't accurate. Buy it and get you some 7mm wby ammo and go at it!
     
  6. Bravo 4

    Bravo 4 Well-Known Member

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    That action could take a lot of abuse, but I would either send it to Weatherby or a competent gunsmith for a good once over before I pulled the trigger on that dude.
     
  7. elktaxi1

    elktaxi1 Well-Known Member

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    we do it every time my buddy runs out of wby brass. we fire form brass in his wby we run120 at 80% works great and way cheaper.
     
  8. MudRunner2005

    MudRunner2005 Well-Known Member

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    Hate to revive an old thread, but I just talked to my smith, and he has a stainless 7mm Wby take-off sitting around his shop that he could put on my .338 WM, since it won't group at all. Said he'd take care of me on all the truing and labor, bedding, floating, and all that stuff, too, so I should be making a smooth getaway with a top-tier custom rifle for about $600 total investment (rifle, rebarreling, truing, & labor). Scope, rings, bases, and other misc stuff were all sitting around the house, B&C Medalist stock came on the rifle when I bought it used, so all it needs is some action massaging and a new tube. It will be a budget build, for sure, but my smith treats every rifle the same, no matter how cheap or how expensive, so everything should turn out perfect. :D

    Anyway, I have a BUNCH of 7mm RemMag brass sitting around. And plan on using this rifle for hunting whitetails this year, as my main hunting rifle.

    The reason for dragging this one from the depths, is that he mentioned that I could fireform 7RM brass to make 7Wby brass for my handloads.

    Is it safe to shoot full-power 7RM factory ammo (have a good bit of factory stuff laying around, too), or would I need to load down and use the cream of wheat method, or something like that? That seems to be a really messy pain in the ass, which is why I was wondering about the 7RM in the 7Wby chamber...

    Thanks
     
  9. MudRunner2005

    MudRunner2005 Well-Known Member

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    Nobody has any experience with this?
     
  10. lloydsmale

    lloydsmale Well-Known Member

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    buddy did it in his. Said it was cheaper to buy rem 7mag ammo then 7 wby brass. One shot and it was fireformed perfectly. I dont know what kind of accuracy he got though.
     
  11. MudRunner2005

    MudRunner2005 Well-Known Member

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    Thanks Lloyd! Good to know.
     
  12. Stonewall2

    Stonewall2 Well-Known Member

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    Check the neck diameter first .
    The 7 mm Weatherby chamber neck is tighter than the 7 mm Remington chamber.

    see here:

    SAAMI | Sporting Arms and Ammunition Manufacturers' Institute

    I would use the Remington brass to make 7 mm Weatherby cases then load and fire form .

    Actually I would use Weatherby or Norma cases as they are very high quality.

    And I LIKE forming brass,turning necks etc.
     
  13. MudRunner2005

    MudRunner2005 Well-Known Member

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    I'll probably just order 100 Norma 7mm Wby brass. It's only about $150 or so from Midway.

    I still have my 2 7mm RM's, so I'll just save that brass for them.

    Plus I'm really OCD about having correct headstamps.