45/70 IMR3031 and pistol primers?

[makicjf]

I have zero (0), nada, not a one, large rifle primers. I have been tinkering with 15 grains unique, a large pistol primer and a lee 405 ww w/d in a marlin cowboy 45/70 and getting good results ( if I would quit bumping the tang sight and changing the setting they might be consistent!:veryconfu). I am down to 2 lbs of unique, and load for the 45 colt, 45 acp, a .38 and cowboy loads 30/30 with unique. I have 2 lbs of imr 3031 and would like to use a lbs to load some lighter loads in the 45/70: I do not know if the pistol primer would be a wise , or safe, substitution under a rifle powder. Unless someone wiser than I says its ok, I'll continue my search for unique or large rifle primers ( actually both) and abstain from using a large pistol primer behind a rifle powder.
Thanks!
Jason

[runfiverun]

if your firing pin will reach the lp primer, and your pressure is under the max pressure a revolver round is specced for [I go about 35-40k] you have no issues except ignition.
i'd proceed carefully, but i'd do it.

[makicjf]

Thanks! this is a pretty low pressure round, well under the ruger only loads in 45 colt. I have been using lp primers with the unique, so I know the pin will reach. I will use some magnum primers and see what happens.
Thanks!
Jason

[makicjf]

Thanks guys! 35 grains of our 3031 a 405 and a large pistol magnum primer worked perfectly!
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