"Weapon", as used in Part 331, means any instrument that is capable of producing death or serious bodily injury when used for its intrinsic purpose or that has the potential to cause serious bodily injury or endanger a life because of the way it is used, the way it is attempted to be used, or the force with which it is used. The term "weapon" includes, but is not limited to, firearms, knives, clubs and explosive devices. (R 331)