The result of your conversion between grain/ounce [UK] and ounce/gallon [US] appears here
To convert between Grain/ounce [UK] and Ounce/gallon [US] you have to do the following:
First divide ((0.45359237/16)*(192/175)/480)/(0.00454609/160) / (0.45359237/16)/0.0037854118 = 0.30452085
Then multiply the amount of Grain/ounce [UK] you want to convert to Ounce/gallon [US], use the chart below to guide you.
Symbol: gr/oz
No description
Symbol: oz/gal
No description