I looked around for a while and I found a Paper from the Cranfield University, called “Ballistics of 17 Century Muskets” from one David Miller. I just took a glimpse, but it seems to speak about muzzle velocity, tactics, gunpowder, materials and so on. It’s a PDF, here’s the link, fresh from google:
Click me!
It’s a Thesis for a MSc, so I’d assume it’s fairly accurate.