Mixing diferent Lots of the same Powder

[Rocky Raab]

I appreciate your concerns, roundball, but the practice of mixing the last dribbles of powder in with the new can (of the exact same powder) is not dangerous in any way.

If the old can of powder wasn't dangerous, and the new one isn't dangerous, how can mixing them suddenly make it dangerous?

Again, if there are minor differences in burn rate, the only thing that can happen is that the new powder is moderated a bit by the old. If it's mixed thoroughly, there could only be one or two kernels of the old in any single charge of the new - and that's isn't enough to matter.