How did machine guns change World War 1?

Answer 1

The basic tactics used in World War I were centuries old - mass charges into enemy positions. In spite of being proven obsolete during the American Civil War - where the lethal range of weapons such as the Springfield Rifled Musket and the rapid reload and firing times of weapons such as the Sharps Carbine led to the devastation of these formations - many countries continued using these tactics. The machine guns of WWI could fire anywhere between 400 and 600 rounds per minute, which meant a charging formation of troops was essentially running into a wall of lead, with a devastating end result. Given the obsolescence of these tactics, the war soon ground into a stalemate.