Also the finer the granule size, the more energetic will be the powder. FFFg is more energetic than FFg so long as we are talking the same powder brand and type. If you sighted in with 100 grains by volume of FFg and then switched to FFFg, you would need to reduce your powder charge about 10% to achieve similar performance.

There are many variations in powders so far as strength of charge. Goex black is much less energetic than Swiss black, for example. Pyrodex is more energetic than some black and less than others. Triple7 is probably the hottest - a contest might be in order between it and Swiss black.

And then there are pellets - a whole different set of rules apply.