What is 'gun' in Latin?

Tormentum may be one translation of 'gun' into Latin. Tormentum tubiferum may be another translation. The Word 'tormentum' is the classical Latin term to describe a stone throwing machine. But guns have barrels. Just in case 'tormentum' doesn't convey equipment including barrels or tubes, it may be more accurate to say 'tormentum tubiferum', which describes the 'tormentum' as 'carrying a tube'.