If someone has some BlackMag3 AND Blackhorn209, I would like to know if a little experimentation with a small charge of BM3 under a larger charge of BH209 would cure ignition issues... not that I would suggest anyone actually do such a thing.
One thing about BM3 is that almost anything will ignite it. Someone elsewhere (I think) mentioned duplexing with a bit of BP. That seems counter to the purpose of using the BH209 in the first place, to me at least. BM3 wouldn't add the negatives - in my estimation.
DISCLAIMER:I haven't a clue what I'm talking about and accept no responsibility for anyone tryiing such a ridiculous experiment. Get it?