416 Rigby brass strength?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Brent, Nov 15, 2001.

  1. Brent

    Brent Well-Known Member

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    I've read about the Rigby brass not found strong enough when the .338 Lapua was being developed. Does anyone know where and how it was found weak?

    I`m guessing Darryl and others who load it up are in the 60-70k psi range. Are the Weatherby cases stronger and last longer.

    BTW, Darryl what do your hot loads in the 338/416 do that make them unusable after 3 loadings, primer pockets loose, cracks?

    Why on earth did they shorten the Lapua?
     
  2. Darryl Cassel

    Darryl Cassel Well-Known Member

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    Brent

    There is no belt on the 416 Case.

    When using extremely hot loads, the web area will expand just like a case with a belt does.

    The die (Like most dies)does not come down far enough over the bottom sides of any case to reduce this expansion.
    With the expansion it also causes the primer pocket to expand which I can fix, that's not the problem. The problem is the web expansion, it makes for hard extraction and entrance of the case into the chamber.

    This also happened to the 378 Weatherby case when I used the 338/378 and the 30/378 and hot loads.

    With the 300 gr, I have found that if I reduced my speed by 100 to 150 FPS I could add much more life to the brass and with the high BC of the bullet, you don't need the speed I originally thought I did.

    Later
    DC
     

  3. Brent

    Brent Well-Known Member

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    Thats exactly what stopped me after about 8 reloadings of my Norma brass. The primer pockets were just slightly loose but extraction was increasingly more difficult with the same load.

    Just curious, how do you fix loose primer pockets?