.338-.378 KT info?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by herr1911, Sep 13, 2010.

  1. herr1911

    herr1911 Member

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    Does anyone play with the .338-.378 Keith-Thompson? Came across a rifle chambered for it, and I'm trying to learn a bit about it- good, bad or otherwise- before I invest much time or money. Also looking for dies to reload for it.
    -Thanks
     
  2. Camshaft

    Camshaft Well-Known Member

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    The .338-.378kt was the wildcat the the. .338-.378weatherby was based off of. Pretty much identical other than the shoulder dimension. Should outpace the edge and lapua by a couple hundred fps. Midway stocks rcbs dies for them if I am not mistaken.
     

  3. herr1911

    herr1911 Member

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    Whay is the best way to get brass for such a thing? Can you modify the factory weatherby cases, or would I need to start with fresh .378 cases? How are these things for accuracy? I understand that the velocity may be impressive, but will they go where you want them to? I'm guessing that a 30+ inch tube would be required for this to perform?
     
  4. sambo3006

    sambo3006 Well-Known Member

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    The 338-378 KT was designed by Elmer Keith and Bob Thompson in the 1960's as a long range elk cartridge to be used with 4831 (I believe Hodgdon) powder, as it was the slowest powder available at the time. They kept the Weatherby double radius shoulder but shortened the case 1/4" to better suit case capacity to the burn rate of 4831. Performance mirrors the modern 338 RUM. Case trimming and forming dies are required to form brass. 378, 338-378 and 30-378 Weatherby brass would all be suitable for case forming. It was an awesome round in its time and still is but the question is whether you want to spend the time and effort to make cases for a round whose performance is duplicated by a modern round. Definitely high on the cool factor, though!
     
  5. Long Time Long Ranger

    Long Time Long Ranger Well-Known Member

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    If you are looking for a big 338 the wildcats off the 378 wby case with the shoulder pushed forward and changed to the standard shoulder do very well. Also look at one of the 338-416 Rigby wildcats. If you are doing a custom big 338 these are the tops and will exceed the lapua and 338-300 ultramag that some on here call edge and several other names by up to 300 fps. I have seen them exceed 3200 fps with a 300 grain bullet and 30"+ barrels.