I did some ongoing research with the Pyrodex, Cap'.
Fell in with a group of people who do a bit of safe experimentation.
Since 5gns black can be used as a booster charge, according to these folks, the stuff can be mixed 1:10 black/Pyro and stored.
I saw them do it. Then I tried it. Worked great. No delays at all, and it seemed more energetic and a bit cleaner than black. No swabbing required.
According to the going theory, delays are caused by the fact that Pyrodex burns, while black explodes. With a cautious mix a few kernels of 2Fg in with Pyrodex RS, the 2Fg catches the spark from the cap and ignites consistently, but the individual kernels are not close enough to each other to create an explosion. It just helps the Pyrodex burn, and Pyrodex is close enough to real black that it doesn't matter if the two are mixed.
Folks are hesitant to use it on T7 but allow it would likely work. BH209 is a different animal altogether, as is the vitamin c based stuff, so we're simply not going there.
I don't recommend anyone try this. I'm learning from a group of folks who think like me -- we're all a bit nutz. Pyrodex says the booster charge is safe, but says nothing about mixing the booster charge with the Pyrodex. Be safe.
The 1:10 Pyrodex is being stored (doesn't seem to be unstable in storage if there's a booster charge in it for some reason or another we're still exploring). I still use Goex 2Fg for regular shooting.
Josh