Im new to the whole firework making business

I bought the following stuff today to start making my own Bangers (Firecrackers if u call them that):
Stone Tumbler / Polisher Machine (2x 1.5 lb) ST4
2-1/2 Lbs. Fireworks Chemical Mill Grinding Media Balls
2000g SALT PETRE
400g Sulfur Powder V fine and 99.9% pure
I have been trying to find charcoal powder do buy (as its the only thing left i need , i think anyway).. my question is this
Will activated charcoal powder work?
Another thing i wanted to ask is.. what does magnesium ribbon do for making fireworks? reason
i ask is i seen a guy say he bought it for making them..
Sorry for the newb questions n thanks