Question about switching Primers ...

rustyinbend

GySgt USMC 1976-1992
Full Member
Minuteman
  • Dec 9, 2018
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    Bend, Oregon
    I'm going to do some testing regarding switching from magnum to standard large rifle primers since I have way more of the latter, than the former. For anyone that's gone from magnum to non-magnum in 300-WM and 300-PRC ... you guys have already answered that it's no big deal, and sometimes even "better". My remaining question is ... Would I expect the velocity to decrease and as such, bulk up the charge weight a bit for my early tests, and if so ... how much (5%, 10%, other)?
     
    i would start with your existing charge and maybe load a other test sample .3 to .5 grains more (or load two more samples at .3 and .6 grains more than current charge weight) and see how each performs. Then go from there.
     
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    Reactions: Baron23
    i would start with your existing charge and maybe load a other test sample .3 to .5 grains more (or load two more samples at .3 and .6 grains more than current charge weight) and see how each performs. Then go from there.
    Good advice ... re-do a short ladder starting at my existing reference load. Makes sense.
     
    I had to charge up by .2 for my 300 prc, but then I found more magnum primers. My SD's weren't as good one I switched from magnum primers