300 RUM Primer question

Discussion in 'Reloading' started by trg41chris, Apr 21, 2010.

  1. trg41chris

    trg41chris Well-Known Member

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    Dec 5, 2008
    I have a question about fired primers in my new PSS. The load I used is 91gr Retumbo with 190smk, COL is 3.603. The primer has a raised cirle around where the firing pin hit. This is the first time to work with this caliber so I do not know if that is normal or a sign of over pressure. The load is pretty mild so I hope this is not the problem. I had no problems ejecting the cases and it was accurate. Any advice will be great. Thanks.
    The rifle has a break and the brass looks fine after firing.
     

  2. Tikkamike

    Tikkamike Well-Known Member

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    Dec 26, 2009
    Nope you are probably fine. Some rifles make the little crater in the primer some don't. Just note the shape and size of your crater and if it starts to change that may be a sign of pressure. The things I watch for over pressure are
    1 Sticky bolt
    2 Shiny spots on head stamp if they start appearing or get worse or smear
    3 Case head expansion they say about .001 is all you want to experience
    4 Primer pocket expansion. once you hit .2085 they will start being quite loose
    5 Velocity
    Keep going with what you are doing.
     

  3. trg41chris

    trg41chris Well-Known Member

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    Cool, thanks.
     
  4. bassin93

    bassin93 Well-Known Member

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    Jan 31, 2009
    My sendero in 300rum does that also, and does not matter how hot or mild the loads are. I use 96 grns of retumbo behind the 208 A-max and the 210 berger. The primers are flattened just to the edges but still have rounded corners but even with the load I started with at 92 grns the primer still flowed back into the firing pin hole. The hole is too large for the pin diameter. Just some of remingtons quality control downgrade.