Dale,
I’ve only used Pyrodex, both RS & P & real BP (Goex FFF). I have found the P granulation the less fouling. But I have found Pyrodex, either granulation, much less fouling than BP.
Why do you not like Pyrodex? Not arguing, just very interested in your thoughts and experiences. I haven’t shot MLs in years and not sure 777 was even yet available. My ML rifles are both sidelocks.
Pyrodex has always given me fits for it's propensity to misfire... especially in the RS granulation... with traditional side-lock guns. I also didn't like the marketing ploy about it not being corrosive at all, not being as corrosive as black powder and that it eliminates any need to clean the gun after shooting.
Much of this comes from my experiences dealing with angry customers who had a misfire while deer hunting... and there were lots of them... but also my own experiences with it. I find that it works OK with inline guns... including percussion revolvers, but so does 777, and with much less fouling and much less post-shooting corrosion because it contains no sulfur. I like to sight in the gun, clean it, fire a "fouling shot" and then leave it alone until after the season is over or after I shoot a deer. You can do this with 777, but not with Pyrodex and perhaps not with black powder either. Nothing is perfect.
I've had the same experiences as far as misfiring with 777 in the 2f granulation, but going to 3f seems to mitigate that issue greatly. I don't really like the "crud ring", but can live with it as I seldom shoot more than ten shots in a string.
I can't say I have noticed any less fouling with Pyrodex over actual black powder, but in recent years I have been using Old Eynsford 3f... which I am rapidly running out of... and all black powder is not created equal.
Basically, I view Pyrodex as having all the disadvantages of black powder (fouling, corrosion), at double the price and with a propensity to not go boom when it is supposed to. Do I use it? Not by choice, but I have and do use it when nothing else is available or when I happen to acquire some very cheaply or free. Right now I got one horn full of Pyrodex P with a bit more left in the bottle it came in. When it is all gone, I will not be replacing it unless I am forced to by circumstance.
Today I picked up a pound of 2f 777 at Cabella's. I was not happy with the price, nor the granulation, but nobody else in town seems to have any at all and it is better to have something to shoot... even with the need for a black powder duplex load... than to have nothing at all.
As soon as Goex goes back into production, I will hopefully acquire ten pounds of Old Eynsford, which might last me for the rest of my life.