the first rapid fire gun was the hand crannked gatling gun used in the civil war but the maxim was the first true machine gun which was developed not long after the gatling
Yes, machine guns were used in WW2.
machine guns and rifles
Did you want to know what calibers were used in machine guns or perhaps what cartridges are for machine guns only.
All sides already possessed them before the war.
Efficiency
The first machine gun was the gatling gun, invented in 1861 There were a variety of multi barrelled guns invented prior to this, but they are not considered to be machine guns.
it used machine guns
Machine guns were first used in the trenches of the First World War. They were mainly used as defensive weapons because they were too heavy to carry, and they required three or so men to operate them. The first true rapid fire gun, the Gatling gun, was used after the Civil War in engagements against Indian tribes.
Every country
Used extensively.
All of them.
All of the major players possessed machine guns by the outbreak of the war.