Painkiller? Not sure about that.
However, there's a bunch: Grave Digger, Rage, Lost Horizon (debut album is UTTERLY godly), Attacker...etc, and then there's a whole host of bands that border on the true/epic style (bringing in the manowar influence) like Battleroar, Manilla Road, Airghed L'amh, etc.
It's all "heavy metal".
Don't get me wrong -- I like Stormwarrior, I'm just surprised that other people around here like it too.