This early style handgun was the beginning of the end for the heavily armored knights. It was fairly simple to use, somewhat inexpensive to produce and deadly at close range. A hit would punch through most armor, giving common infantry a deadly way to deal with expensive knights. Cheap and fast to learn (hand gunners could be trained in weeks vs the five or more years it took to train a longbowman) were added bonuses. Soon armies would begin to rely on improved matchlocks that would take control of the battlefield.
This heavier "hand cannon" gave the Middle Ages infantry brutal killing power, at close range. The dawning of the age of gunpowder was at hand. Warfare would never be the same.