What with those weapons?

[Honorable Discharge]

Is there any manuel explaining how the weapons work? I'm used to Painkiller, but Overdose? Not so much, so I think I'm not really getting the hang of those exotic weapons.

For example, the broken sword. Sometimes the skulls it fires at autoguided toward enemies, sometimes not.
And what about that bonegun? Is its range like the shotgun's or is it way shorter?

[Paranoic]

Seems bonegun deals more dammage,and it is more powerfull then a shotgun,since you can freeze enemies faster,shoot bones-bullets faster and more chance to gib an enemmy.