YOU will never get Goex to burn clean but Goex likes .300 to .375 compression THAT'S a good place to start. Swiss powder .100 to 225 is what I've found but you need to run the loads over a Chrony to find the sweet spot on the compression other wise your shooting in the dark.
Walters veggies cards .30
But if I HAD NO CHRONY my best bet would be .350 for the Goex and .150 on the Swiss for compression