The result of your conversion between grain/ounce [US] and ounce/gallon [US] appears here
To convert between Grain/ounce [US] and Ounce/gallon [US] you have to do the following:
First divide ((0.45359237/16)*(192/175)/480)/(0.0037854118/128) / (0.45359237/16)/0.0037854118 = 0.29257143
Then multiply the amount of Grain/ounce [US] you want to convert to Ounce/gallon [US], use the chart below to guide you.
Symbol: gr/oz
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Symbol: oz/gal
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