300 imperial magnum what is it ??

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by denny r, Dec 10, 2011.

  1. denny r

    denny r New Member

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    i see one for sale and don't know anything about it...is it a wildcat/ or factory.. /are dies available or where can i find more info, this rifle is a sako m995 trg-s , and the price is right...THANKS,Denny
     
    Last edited: Dec 10, 2011
  2. brentc

    brentc Well-Known Member

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    The imperial is essentially necked down and formed from a full length 404 Jeffery case. The imperial precedes the RUM and is the idea in which the RUM was based. Performance will be comparable with the 300 RUM even though powder capacities may be slightly different between the two chamberings.
     

  3. Cornfield Flats

    Cornfield Flats Active Member

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    Exactly correct. I've had a 338 Imperial since before the Ultra Mags were introduced. They are excellent cartridges. I now use 375 Ultra Mag cases to form the 338 Imperial.
     
  4. denny r

    denny r New Member

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    where can i find more info...i didn't explain myself first time around..did norma make this one?
     
  5. 436

    436 Well-Known Member

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    From an old friend of mine... Ret. RCMP Aubrey White the designer of the cartridge... it's a very fine design in any of its many calibers; Aubrey was way ahead of the times with this one.

    Here's his email; rifle@persona.ca

    North American Shooting System
    11 Rose Place RR 1
    Osoyoos, BC VOH 1V1
    (250) 495-3131

    Cheer’s
    436

     
  6. phorwath

    phorwath Well-Known Member

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    "Origin & History

    In the early 1980s Aubrey White and Noburo Uno of North American Shooting Systems (NASS) based in British Columbia Canada began experimenting with the full length .404 Jeffery by reducing the taper and necking it down to various calibers such as 7 mm, .308, 311, 338, 9.3 mm and .375. These cartridges were known variously as the Canadian Magnum or the Imperial Magnums. Rifles were built on Remington Model 700 Long Actions and used Macmillan stocks. Cartridges were fire formed from .404 Jeffery cases with the rim turned down, taper reduced and featured sharp shoulders.

    Both Remington and Dakota Arms purchased the formed brass designed by Noburo Uno for use in their own experimentation and cartridge development. In 1999 Remington released the first of a series of cartridges virtually identical to the Canadian Magnum cartridges which featured a slightly wider body, increased taper, and shallower shoulders and named it the .300 Remington Ultra Magnum. Dakota too released their own version of the cartridge but chose not to turn down the rim and shortened the case to work in a standard length action. Remington would go on to design their own shortened versions of the Ultra Magnum cartridge which they were to call the Remington Short Action Ultra Magnum or RSAUM for short."

    Here's a link. I used to own and shoot a .338 Imperial Magnum. That rifle is now a .338 Edge, which is the .338 Imperial with the shoulder pushed further forward by about 0.020".

    .300 Remington Ultra Magnum - Wikipedia, the free encyclopedia
     
  7. denny r

    denny r New Member

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    thank you, guys for all your help!!!!! just what i needed to know..denny
     
  8. rayhuggart

    rayhuggart New Member

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    the 300 imperial was developed by a canadian there was 2 versions im not sure witch was first the 300 canadian or the 300 imperial, the 300 ultramag is a very close copy,i personally was going to build one but the ultra mag came out befor i could find a good left hand acrtion to use.
     
  9. FEENIX

    FEENIX Well-Known Member

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    Cool! We have two claims, let's hear it! :D:rolleyes::cool:
     
  10. jcheckland

    jcheckland New Member

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    i called the number on your comments about North American Shooting Systems, it said the number is no longer in service. Do you have another number for them, if not do you know who manufacturers the Imperial band of rifles and how much they might be.
     
  11. 436

    436 Well-Known Member

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    I'll check and get back with you by PM
    436
     
  12. jcheckland

    jcheckland New Member

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    Thanks I appreciate it. Any further information on the subject would be appreciated.
     
  13. J E Custom

    J E Custom Well-Known Member

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    It is most likely a wildcat and chamber dimensions can vary depending on the reamer dimension
    and the designer.

    The simple solution would be to check if the chamber could be set back 1/16th and if it would clean up using a 300 RUM SAMME Reamer.

    The 300 rum uses the same case head size as a magnum and there should be plenty of brass in the future for the RUMs.

    If you buy the 404 Jeffery cases you will have to turn the case heads down (Not an easy task) But if everything is close enough to the RUM and the case head is correct, all you have to do is fire form
    with RUM Brass.

    J E CUSTOM