That's a real nice photo there, Smokin Gun!
Yeah, it is a sense of humor all right. In real life I would never not have some sort of measure to dispense black powder. Even with flasks I have a pretty good idea of the grain amount - from putting it in a measure!
Justin Wilson had his own cooking show in the last century. There are still some cookbooks available. One of the things that he did do was to measure teaspoons of salt in his hand on TV, and when he poured it into a teaspoon measure, it was right on the mark. Another one of his trademarks was to pour some Louisiana Hot Sauce into his recipes, and then pour more in. I also understand that he was a hunter, too. Don't know if he did black powder, though, but I bet he would have that grain weight right if he tried it!
The Doc is out now.