The result of your conversion between grain/ounce [US] and ounce/cubic foot appears here
To convert between Grain/ounce [US] and Ounce/cubic Foot you have to do the following:
First divide ((0.45359237/16)*(192/175)/480)/(0.0037854118/128) / (0.45359237/16)/((0.0037854118/231)*1728) = 2.18858627
Then multiply the amount of Grain/ounce [US] you want to convert to Ounce/cubic Foot, use the chart below to guide you.
Symbol: gr/oz
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Symbol: oz/fm³
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