Mixing real blackpowder with 777 produces volatile results. That is why Hodgdon Inc has never put real blackpowder on the bottom of their 777 pellets like they do with Pyrodex pellets. Blackpowder-flintlock panning is acceptable with 777, but anyone using percussions reading your post should never mix both powders & pour down the muzzle.

I always feel the need to mention this whenever I read the two powders were used simoutaneously. Sadly, readers misinterpret posts too much & danger sometimes looms later-on. This book below is supposedly great for load development. I just ordered mine because I'm about to get heavily into real blackpowder (Swiss).

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