<P> The paper cartridge was introduced sometime before 1586, and the bayonet came to use in 16th century France . Hand grenades, thrown by grenadiers, appeared around the same time . </P> <P> Early cartridge firearms had to be cocked and caught by the "sear", which holds the hammer back, before each shot . Pulling the trigger allows the hammer or striker to fly forward, striking the "firing pin," which then strikes the "primer," igniting an impact - sensitive chemical compound (historically, first fulminate of mercury, then potassium chlorate, now lead styphnate) which shoots a flame through the "flash hole" into the cartridge's propellant chamber, igniting the propellant . </P> <P> The Springfield Armory in Springfield, Massachusetts became important to the history of firearms during the 1850s, when it debuted the Springfield rifle . Springfield rifles were among the very first breech - loading rifles, starting production in 1865 . By that time, metallurgy had developed sufficiently so that brass could be worked into fixed ammunition . Previously, each round was custom made as needed: the shooter poured loose powder down the barrel, used leather or cloth for wadding if time allowed, selected a suitable projectile (lead ball, rocks, arrow, or nail), then seated the projectile on top of the powder charge by means of a ramrod . Performance was erratic . Fixed ammunition combined a primer, the pre-measured charge, and the projectile in a water - resistant brass cartridge case . Most importantly, the soft brass expanded under pressure of the gas to seal the rear end of the barrel, which prevented the shooter from being maimed by escaping high - pressure gas when he pulled the trigger . </P> <P> A repeating firearm or "repeater" is a firearm that holds more than one cartridge and can be fired more than once between chargings . One example of a repeater is the American Springfield Model 1892--99--also made at the Springfield Armory in Springfield, Massachusetts--which were used during the Spanish--American War . Some repeating firearms require manipulation of a bolt (as in bolt action), lever, or slide to eject the fired cartridge case, draw a fresh cartridge from the magazine, and insert it into the firing chamber, and "cock" (draw to the rear and place under spring tension) the hammer or striker, so that pulling the trigger will fire the weapon . Others use either the firearm's recoil or a small portion of the propellant gas drawn from the barrel, to operate the firearm's mechanism and ready it for the next shot . Such firearms are sometimes called "self - loading," but are more commonly known as semi-automatic, if they fire one shot for every pull of the trigger, or automatic or "full - auto" if they continue to fire until the trigger is released and the magazine is empty . </P>

When was the first gun used in war