Listen to folks who have years and decades of experience in ths hobby.
1) tools and equipent and high grade raw materials are likely to require much more of an investment then say a couple of cases of BP from one of the on-line dealers. And you still have to make it all work together. Unless you work at Disney and are firing every day or weekend, you have a lot of catching up before you break even - if ever - see note #2.
2) See as how BP is an explosive and not an accelerant like smokeless powder, it is subject to detonation by pressure.Whack a grain of BP hard enough and it will explode. In order to make good BP, there is a certain amount of grinding to acheive the right grain size. If not done by proffessionals - you will go BOOM.
3) Quadruple your house insurance, but DONT tell the Ins company why. An ex GF woked for a BIG insurance company, one of the few female underwriters at that time. She got fired for wrting a policy for a fireworks factory. It later blew up. Grucci, the best known fireworks maker in the USA, if not the world, lost a factory same way. It blew up.
4) Let us all know where you live, because I certainly do not want to live next door to someone who is making homemade black power, and I daresay no one else does either.
Advice - if you need that much Goex, there are discounts available for large purchases ( up here in NY and New England , that is limited to 50 lbs).
Good luck. Seek ye the web board on greybeardoutdoors, they have a specific one for black powder cannons.
http://www.go2gbo.com/forums/index.php