I've been shooting 85 gr. of 2f goex with a.530 round ball and getting a velosity of about 1400 fps. I used up all my goex so I got out my can of 2f swiss I've been saving. I used the same volume measure I used for the goex. What a surprise! Vlosity went up to 1650. I guess if a person was using a max load of goex, he might ought to reduce the swiss startup load. The 2f swiss looks like 3f goex. Anyway my barrel has had 300 gr. of 2f goex and 2 round balls for a proof load. The swiss load did shoot a tighter group