History has hundreds, if not thousands, of examples of odd weaponry. The gun swords (I kid you not, someone actually made gun swords) and gun daggers are examples of this. There were even gun shields (shields with a gun in them, no kidding) produced at one time.
Remember, powder weapons are actually thousands of years old. It's only recently that technology has allowed them the premeire spot in the world's arsenals.
EDIT: Spelling, need a spellchecker.