The result of your conversion between Iron and grain/quart [US] appears here
To convert between Iron and Grain/quart [US] you have to do the following:
First divide 7658 / ((0.45359237/16)*(192/175)/480)/(0.0037854118/4) = 111840.93823646
Then multiply the amount of Iron you want to convert to Grain/quart [US], use the chart below to guide you.
Symbol: iron
No description
Symbol: gr/qt
No description