At the Varnum Memorial Armory Museum we have an exceptional example of a World War I Lewis light machine gun originally designed by an American, Isaac Newton Lewis, but rejected by US Ordinance. Lewis took his design to Belgium, where it was received with some enthusiasm. Prior to the fall of Belgium to the Germans Lewis fled to Britain, where the design was licensed to BSA. It became the standard light machine gun of the British Expeditionary Forces and was much loved by both British Tommies and the German forces who regularly turned captured Lewis Guns on their former owners.
This variant at the Varnum Armory was manufactured by Savage Arms in the United States as the Model 1917. In US service, they were primarily used for training. In fact, from the Second Division paper from 1919 we have a reference to the 6th Marines turning in their Lewis Guns when they arrived in France and being issued French Chachaut light machine guns for battle.
Feeding from a 47-round “pan” type drum magazine, the Lewis Gun had a unique cooling system. The large shroud over the barrel covers an aluminum radiator, a mass of fins that are designed to act as a heat sink, keeping the barrel cooler when firing. The muzzle is also recessed into the shroud and the shroud is open at the rear, near the receiver. It was intended that the gasses exiting the muzzle would draw cooler air in from the rear and cool the barrel and radiator. While somewhat effective, the added weight and manufacturing cost made the overall benefits less significant. The aircraft version, which was used throughout the war, dispensed with this feature and was very successful.
The Lewis Light Machine Gun was an enduring design and continued in military service, albeit in a limited manner until the late 1950s. The basic design of the Lewis Guns bolt and operating rod mechanism was used in the famous M-60 machine gun, the standard machine gun of US forces from 1957 to the early 2000s.