The result of your conversion between pound/cubic foot and grain/cubic inch appears here
To convert between Pound/cubic Foot and Grain/cubic Inch you have to do the following:
First divide 0.45359237/((0.0037854118/231)*1728) / ((0.45359237/16)*(192/175)/480)/(0.0037854118/231) = 4.05092593
Then multiply the amount of Pound/cubic Foot you want to convert to Grain/cubic Inch, use the chart below to guide you.
Symbol: lb/ft³
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Symbol: gr/in³
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