How do you do the scrake stun with katana or axe? Ive heard for Katana you have to alt fire to the head but it never works for me and i always see other bezerkers doing scrake stun with Katana. Also what is the axe good for? Ive seen on youtube people using the axe against FPs hitting them with it then backing up so it doesnt hit you and then repeat. I was also wondering exactly how to do this and if it can also do other things.
btw im only lvl 2 bezerker

but lvl 6 Support , Medic and Sharpshooter
lvl 4 demo,Commando and Firebug.
A Scrake is stunned when you deal a certain amount of damage to its head in a single blow. Things that can do that are
Axe alt fire head shot from a level 5+ berzerker
Axe primary back stab from a level 5+ berzerker
Katana alt fire backstab from a level 4+ berzerker
Axe alt fire head shot from the back for any perk
And a chainsaw alt fire is pretty much interchangeable with the axe wherever you see it on this list.
I don't keep up with patches as much as others so this list may be a bit off, so someone correct me if I'm wrong.
As for what is the axe good for? It's basically used whenever you need power coupled with mobility but, have no need for attack speed.
EDIT: Looks like someone beat me to it by a bit, anyway come to think of it I can't remember if it's percentage based or even if it has to be head damage.
EDIT AGAIN: I did some quick research and heard you have to do about 666 (Ha!) damage in a single blow to stun a Scrake. Doesn't seem to need a headshot either.