If you're asking whether it's legal to make your own black powder, it is legal.
It is not a violation of
Federal Law to make black powder for sporting or educational purposes. The
Federal Government allows you to possess up to 50 lbs. (total)
So if you had five pounds of commercial powder, and then made 50 lbs. of powder, you would be five pounds over the
Federal Government limit.
You cannot trade it away, nor give it away, nor sell it.
Now when it comes to illegal or unlawful, you also have your state, your county, and municipal regulations that will mean you are breaking the law while the Feds won't care.
AND THEN for folks who are legal at all levels when making it..., are they complying with state, county, municipal laws when it comes to
possession and
storing it ??? There are folks that might be in a situation where they are told "Nope, not illegal here it make some Black Powder", only to find out that they made too much OR, for what they made they needed some special (and normally expensive) storage arrangement.
There are several layers to check. Even if you don't make it yourself. For example where I live because I'm in a Townhouse, and not a single family home, my storage limit is different and less than were I in a SFH.
And that, with the reply about the fed regulation, pretty much covers this entire question
LD