The result of your conversion between grain/ounce [US] and Iron appears here
To convert between Grain/ounce [US] and Iron you have to do the following:
First divide ((0.45359237/16)*(192/175)/480)/(0.0037854118/128) / 7658 = 0.00028612
Then multiply the amount of Grain/ounce [US] you want to convert to Iron, use the chart below to guide you.
Symbol: gr/oz
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Symbol: iron
No description