That is a semi-balloon head case.
Solid rim but a folded primer pocket.
Some good illustrations here on the differences.
https://forums.gunboards.com/showthr...oon-head-cases
The powder would be very difficult, if not impossible, to fully identify just given the shape.
However, I have some resources that may provide some insight on what it MIGHT be.
My guess is that it's from Hercules.