Oh, there's some sort of disposition between metal and hardcore. I, for one, do not help that disposition. I, like many others, don't consider hardcore metal and vice versa. There are a lot of differences in the music what with abrupt breakdowns built specifically for mosh pit reaction, solos aren't as common (from what I've heard mind you so no **** please if I'm wrong). Vocal style can vary from emo type wails to blunt screams and in some cases a good growl or two. Friend of mine and I often argue over which is more brutal, death metal or hardcore. I, of course, veer towards death metal and he defends hardcore. Anyway, hardcore tends to move at a reasonable pace. Scales would probably be as common in hardcore as anywhere else though. Some use them, some don't.
The Gods Made Heavy Metal, And They Saw That It Was Good
They Said To Play It Louder Than Hell, We Promised That We Would
Hulk Smash!!
Whatever you do, don't eat limes. A friend of mine ate a lime once and BAM!! Two years later. Herpes.