Volley gun
The Ribauldequin was a medieval version of the volley gun. It had its barrels set up in parallel. This early version was first employed during the Hundred Years' War by the army of Edward III of England, in 1339. Later on, the late Swiss army employed it.
Rifle
Revolving rifles were an attempt to increase the rate of fire of rifles by combining them with the revolving firing mechanism that had been developed earlier for revolving pistols. Colt began experimenting with revolving rifles in the early 19th century, and other manufacturers like Remington later experimented with them as well. The Colt Revolving Rifle Model 1855 was an early repeating rifle and the first one to be used by the U.S. Government, and saw some limited action during the American Civil War. Revolvers, both rifles and pistols, tend to spray fragments of metal from the front of the cylinder.