I have used Goex fffg in my black powder revolvers but would like to use Hodgdon Triple 7. I use flasks with volumetric spouts that deliver a designated weight in grains of powder. I know that Triple 7 weighs less but is more energetic. I also know that grains are weight but since the spouts are made to deliver a certain weight in grains of black powder what conversion factor should I use for Triple 7? For example say I use a 20 grain spout for my Goex fffg what spout size should I use for a Triple 7?