We tried like all get out to answer some of that today, and if the WIND hadn't been so nuts...well, we might know more.
As it is, Da Boy brought out the Hip Howitzer to see what the difference might be between 3F Goex and some LAGS made 3F Toilet Paper powder. I hope the TP was fresh, and not used - that extra smell in the air might be too much.
First, he shot with Goex - for the ones who gave him grief about using light loads like 20-30 grains...he forgot his pistol powder measure at home, so these shots were charged with 60 grains each. That first one got his attention RIGHT away!
However, in his fine tradition...
Now, this is where you use the images above to build new ones in your mind's eye...because my camera took such lousy photos you can't SEE what was going on! But what did happen is he loaded with 60 grains of the TP powder, and fired. He said the recoil was just slightly less, and the ball hit higher. To him and me, the recoil seemed about the same, but it might have been hot rod loads in such a small pistol.
In any case it was just plain fun! But the wind wouldn't even let him pour powder...maybe next time.