1861 - Breech loaded guns in common use. 1861-1865 - American Civil War. Both breech and muzzle loaded guns used. 1862 - The Gatling Gun is invented. 1869 - Center-fire cartridge introduced.

In November 1864, during the final weeks of the American Civil War, a Union train pulls ... the latest military invention of Dr. Gatling, the Gatling Gun. Only four such weapons have been ...