300 WSM primer choice?

Discussion in 'Reloading' started by Guy M, Sep 20, 2007.

  1. Guy M

    Guy M Well-Known Member

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    Have run into a variety of different recommended primers for the .300 WSM in the published and on-line load data from different powder & bullet makers.

    It's certainly not a huge case... What's working? Standard primers? Magnum primers?

    The cartridge is new to me...

    Thanks, Guy
     
  2. Boss Hoss

    Boss Hoss Well-Known Member

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    I use the 215m's for mine. I also use them in my competition rifles so when loading for a sporter if it calls for a mag primer the 215m it is.
     

  3. justgoharder

    justgoharder Well-Known Member

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    I've used CCI magnum large rifle primers for my WSM and they are working well.
     
  4. jeffbird

    jeffbird Well-Known Member

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    Guy,
    I use large rifle primers, F210M, rather than mag primers in the 7wsm which is using a tad more powder than the 300 wsm. The SD is lower and they light fine. If it was for use in freezing temps, I would change over to mag primers. I base this on testing WLR, WLRM, F215M, and F210M's.
     
  5. BountyHunter

    BountyHunter Writers Guild

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    Definitely non magnum, you will bet better accuracy 90% of the time.

    However, try both. No need for the magnum with MRP, H4350, H4831, which seem to be the go to powders for the WSMs.

    BH
     
  6. britz

    britz Well-Known Member

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    used R19, Win 760, IMR 4350 H 380 and H4350. Used CCI 250 mag primers for all. I have to admit that Primer choice is not huge on my list of things to change. I choose a primer that is good for the cal and generally stick with it.
     
  7. overbore

    overbore Well-Known Member

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    Old Rule

    was, for hunting, use a Mag for 4831 and slower powder or freezing temps. For accuracy Large rifle with the lowest S/D is optimum. Overbore