Case fouling on shoulder/neck

Discussion in 'Reloading' started by Namibia, Jun 3, 2010.

  1. Namibia

    Namibia Member

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    Sep 14, 2009
    Good evening Gents,

    Can someone maybe assist me with the following problem. A friend of mine reloads for a .300Win Mag. using Sierra GK 180gr, and Prvi Partizan Brass. He assured me that the charge is well below max according to the manual. (I don't have the exact charge and type of powder though)

    After firing his loads, there's quite a bit of powder fouling on the shoulder area of the case (on the outside of the case, off course:)), as well as on the neck area. Seems like some of the gas is leaking "back" past the neck during firing resulting in a "burnt power residue". This doesn't occur further down the case past the shoulder egde.

    He shoots a Ruger M77 Hawkeye, and the rifle is brand new.

    Your imputs will be much appreciated.

    Thanx

    Pieter
     
  2. jeffro

    jeffro Well-Known Member

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    Quote - He assured me that the charge is well below max according to the manual.

    This will sometimes cause this as the case is not sealing with the low preasures that are produced at low charges.
     

  3. Broz

    Broz Well-Known Member

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    I started to see this before after about 4 firings as the brass was work hardening and not sealing good. This was when I started annealing necks and it curred the problem. So depending on your times fired it could be it.

    Jeff
     
  4. jeffro

    jeffro Well-Known Member

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    That will cause it as well. Good point.
     
  5. Tucker943

    Tucker943 Member

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    Jan 31, 2009
    My Hawkeye 7 mag did the same thing when i was running some hardened brass though it. Fresh or annealed brass will almost certainly solve the issue.
     
  6. J E Custom

    J E Custom Well-Known Member

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  7. trueblue

    trueblue Well-Known Member

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    You were given good answers. All of the above.