The result of your conversion between megajoule and grain/ounce [US] appears here
To convert between Megajoule and Grain/ounce [US] you have to do the following:
First divide 1000000 / ((0.45359237/16)*(192/175)/480)/(0.0037854118/128) = 456389.30789885
Then multiply the amount of Megajoule you want to convert to Grain/ounce [US], use the chart below to guide you.
Symbol: MJ
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Symbol: gr/oz
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