I've tested about every kind of powder out there, loose or pellet. The only powder I can think of that I have not shot is Jim Shockey Gold. The only powder that ever gave/gives me accuracy fits (as it did again today) is American Pioneer Powder. I can make most rifles behave and shoot very well with most powders. Today I was shooting three different powders, two different rifles, four different projectiles. One of the powders of course was APP 2f. What a shock when I shotgroups with that. If you could even call it a group. So I tried the powder two different ways, swabbing between shots, and not swabbing. Both ways, the groups were not acceptable. Even simple Goex outshot APP hands down. My next thing is to try APP in a couple more rifles to see if one of them likes the stuff. I am pretty sure my Black Diamond XR will shoot it, as it shoots about anything you want to shove down the barrel.
Like already said, the powder companies are trying to sell powder. They will promise you about anything they think will make you buy at least a pound of it. So we know this powder is x% stronger then that, but only in loose form... And that powder is only stronger a little in the finer grains.. now there are Magnum pellets.



Makes me more and more want to load a simple flintlock and shoot roundball with Goex... Life was easy back then with just Goex and Pyrodex around. They both shot about the same. They all seemed more then able to meet my hunting needs.
Of course that is also what makes this sport so fun, is trying all the different things out there.