Lian Zi Chong (連子銃)

Drawing of a Lian Zi Chong, from 'Ji Xiao Xin Shu (《紀效新書》)'.

Lian Zi Chong (連子銃, lit. 'Rapid bullet gun') was  a type of rapid fire handgonne developed during mid Ming period. It had a round iron tube magazine mounted perpendicular to its barrel that held several lead balls. Lian Zi Chong was also loaded with several paper cylinders containing pre-measured charge of gunpowder (essentially blank paper cartridges), all connected to a single fuse.

When the fuse was lit, gunpowder charges would be ignited one by one, shooting lead balls out of the barrel one at a time until entire magazine was spent. Once Lian Zi Chong stated firing, there is no way to stop it. In a sense, Lian Zi Chong was basically a Roman candle in gun form.

While this weapon wasn't impractical to the point of completely unusable, it was notoriously weak, inaccurate and unreliable.