Water-Cooled Machine Guns
Machine guns were the new weapon of choice for modern war because they were able to provide sustained fire. In 1917 the United States was just starting to take an interest in outfitting their military with machine guns. The British already had the Vickers machine gun, the French had the Hotchkiss and the Germans had the Maschinengewehr 08. The United States developed the M1917 Browning which was lighter than both of those models and proved to be reliable enough to fire constantly for 48 minutes and fire over 40,000 rounds without failure.
During World War I despite the U.S. government intending for the Browning M1917 to be the main machine gun of the military, they actually depended more on the French Hotchkiss 8 mm. This machine gun would be the one used most often by the American Expeditionary Force. While the Browning M1917 was used only toward the tail end of World War I, it would come into use again in World War II.
During World War II the Browning M1917 was used but it’s purpose was already being transformed. It was used mostly as a fixed gun and not one that was likely to be used by an army on the move. The Browning M1917 was also given to the British in order to replace the Vickers that had been lost in the Fall of France. The Browning M1917 would be used again in the Korean War but afterward most of the guns would be considered no longer useful to the U.S. military and would be left to the South Koreans.
The water-cooled Browning M1917 and other machine guns like it were replaced by guns that used quick changing barrels. The quick changing barrels meant that it would be quicker to keep the fire going without needing to spend several minutes changing the barrel and adjusting the timing. The quick-change barrel system also eliminated the need for a water-cooling system.