Light Machine Gun (LMG)
The famous Lewis Gun was used in all manner of ways throughout World War 1 and World War 2.
Authored By: Staff Writer | Last Edited:
American Isaac Newton Lewis (1858-1931) served in the United States Army and lent his talents to invention when possible. In 1911, he refined an original machine gun design of Samuel Maclean and began active marketing of type which came to be known simply as the "Lewis Gun", "Lewis Automatic Rifle" or "Lewis Automatic Machine Gun". The weapon proved a portable, air-cooled system with multi-role possibilities. Throughout its career, it served as a fixed defensive weapon, an aerial machine gun and as a Light Machine Gun (LMG) at the infantry level. The Lewis Gun went on to serve throughout World War 1 (1914-1918), World War 2 (1939-1945) and was in limited use during the Korean War (1950-1953). Interestingly, the American-originated weapon did not initially interest US authorities when it was first unveiled which forced Lewis to take the development to Europe where he first sold it to the Belgian Army and local production ensued. From there, French and British interest netted Lewis tens of thousands on order and - once America committed to World War 1 - forced the United States to finally invest in the Lewis Gun of which they did. Large-scale manufacture eventually settled to England where it was produced at the Birmingham Small Arms Company, Ltd (BSA) of Birmingham UK. The Lewis Gun became one of many weapons that saw extensive use in both world wars.
The Belgian Army adopted the Lewis Gun in 1913 to which the British Army then followed. In the summer of 1914, World War 1 was sparked with the assassination of the heir-presumtive to the Austrian-Hungarian throne, forcing long-held alliances to come into play with national power committing to war against national power. The German Empire was aligned with Austria-Hungary, the Kingdom of Bulgaria and the Ottoman Empire (Turkey) through the collective name of the "Central Powers". Against them was the "Triple Entente" led by Britain, France and Russia. Britain was sworn to Belgium's aid in the event of war which came in July of 1914. The German intent was to conquer Belgium en route to Paris, France.
The initial German thrust was swift and forced Belgian forces into retreat. It was during this fierce fighting that the Lewis Gun was first pressed into actual combat. The British Army claimed use of the weapon during this time as well, though in fewer numbers than their Belgian allies. By the time the war was in full swing, the Lewis Gun was available in substantial numbers and promptly placed into all sorts of battlefield requirements - including their fitting at observer stations (rear gunners) on tandem-seat "fighting scout" biplanes as well as large multi-engined, multi-position bombers defensed by an array of machine guns on trainable mounts. The war - expected to be over by Christmas of 1914 - extended into a series of bloody entanglements involving trench warfare that would span four long years of bloodshed. The once-fluid fronts had bogged down into a network of trench passages with "No Man's Land" sections established between two competing forces - often competing for nothing more than several hundred yards of desolate landscape.
The machine gun played a significant role in warfare for the first time during World War 1 as it held the ability to single-handedly changed any one engagement in favor of the operator. The machine gun was also joined by the aircraft and "tank" (then known as landships) during this time as well. The repeat, voluminous fire capability of the machine gun allowed for swathes of territory to be under the gun's firing arc and range, keeping the enemy at bay. Machine guns could also be "networked" through two or three individual emplacements covering the other, ensuring multiple arcs and further endangering any brave souls charged with taking well-defended positions. This, along with artillery fire, attributed to the high casualty counts of the war which was still being fought with rules based in 19th Century warfare.
At its core, the Lewis Machine Gun was a gas-operated system weighing some 28lbs. The type was chambered for a series of cartridges throughout its long service life led by the .303 British cartridge and including the American .30-06 Springfield round and the German 7.92x57mm Mauser round. All versions were fed by a top-mounted "pan" magazine and these could number either 47- or 97-rounds in total. Sighting was through a blade and tangent leaf arrangement to allow for some accuracy down range. Rate-of-fire was 500 to 600 rounds per minute and the weapon offered a muzzle velocity of 2,440 feet per second. Effective range was 880 yards with a maximum range of 3,500 yards. The weapon was traditionally given an underslung pistol grip with integrated trigger unit as well as a solid wooden stock. A bipod supported the forward portion of the weapon.
One of the key physical features of the Lewis Gun was its cylindrical forward section which was actually a cooling shroud intended to counter the effects of an overheated barrel. The shroud utilized a "forced cooling" principle in which the rear of the shroud lay open and pulled cooler air into and around the barrel and gas cylinder through a finned aluminum radiator structure. The shroud also covered the muzzle, surpassing its length somewhat and it was at this area that the exiting propellant gasses induced flow of the air through the cooling assembly at the rear, running up and along the radiator arrangement and, in theory adding a cooling feature to the barrel. The shroud allowed the weapon to be an "air-cooled" machine gun which ran contrary to developments such as the storied Vickers model which required use of a water canister and hose attachment for its cooling. While water cooling proved the more effective method (assuming a steady supply of water), it also required extra equipment and required multiple personnel unlike air-cooled guns.
When it was realized that the Lewis Gun made for a good aerial weapon, the shroud was removed without any repercussions to the gun. Many Allied aircraft were then fitted with Lewis Guns at the rear cockpit while Vickers machine guns remained the primary forward-mounted, forward-firing weapons. Such Lewis Guns were typically set on trainable ring mountings allowing for expanded firing arcs.
Lewis marketed his gun to American authorities and, while evaluated by the US Army to some point, the weapon was not adopted as America was not yet pressed with a wartime atmosphere (it entered the war in 1917). By the time of the American commitment, the Lewis system was well-established and proven in combat and - coupled with a shortage of small arms for American forces arriving in Europe - ensured that the United States Army would procure the type in time and in number. At the end of the war, the weapon remained in the US Army inventory though relegated for training purposes - a veteran of one of the first modern bloody conflicts and the first to showcase machine guns in their full, frightful power. American aircraft did, however, standardized on Lewis Guns for a time following the European experience.
The Lewis Gun managed to survive the budget cuts of the interwar years across several militaries of the world. Despite it being replaced in some circles (the British went on to adopt the excellent Czech-based BREN Light Machine Gun), the Lewis series was still in circulation by the time of World War 2. Again, a shortage of small arms forced the aging weapon into frontline service. Even with British BRENs available, so much inventory was lost in the harried evacuations at Dunkirk, France that Lewis Guns in British storage were reissued to Home Guard and naval elements to shore up stock limitations.
In practice, Lewis Guns were highly valued for their lethality though they did prove prone to jamming and excessive weight (particularly for a "light" machine gun). One of the primary reasons for stoppages lay in the overhead pan magazine feed as well as the relatively complex internal action. Regardless, it was available in the required numbers and, when working, it provided the repeat-fire capabilities on land and in the air that was needed by Allied forces. Additionally, a half-dozen or so Lewis Guns could be manufactured for every one Vickers system, such was its comparable manufacture simplicity.
As a long-running weapon, the Lewis Gun appeared in several notable variants throughout its service life. The Mark 1 model was brought about on October 15th, 1915 by the British Army and proved the original production form. These were fielded with the 47-round count pan magazines with sights ranged out to 2,000 yards. Overall length was 50.5 inches with an unloaded weight of 26lbs.
The Mark 2 was brought about as an aircraft-based version of the land-based Mark 1 and these were adopted on November 10th, 1915. The Mark 2 saw its cooling shroud removed and a spade-type grip added to the rear of the receiver (losing its wooden stock). Early versions still utilized the 47-round pan magazine until, in November of 1916, the 97-round count was introduced on aircraft variants as well.
The Mark 2* was adopted late in the war on May 13th, 1918 (the war ended with an armistice in November). Based on the Mark 2 design, and modified from existing stocks of that weapon, the Mark 2* was given a higher rate-of-fire for improved hit probability in aerial combat. This involved use of a dimensionally larger gas port used in the gas-operated action. The Mark 3 designation was nothing more than new-build Mark 2* guns.
Lewis Guns were available in its various forms throughout the interwar years. By the time of World War 2, they were, yet again, pressed into service. The war began in 1939 with the German invasion of Poland, prompting both France and Britain to declare war on the Axis powers with included Italy, Japan, Hungary, Bulgaria and Romania. The German tactic lay, once again, in dominating Belgium and its neighbors en route to Paris, France which was finally reached in the summer of 1940. In 1942, the British Navy headed development of the "Lewis SS" gun (also "Lewis Mark XI SS") which attempted to translate the Lewis Gun into a more conventional infantry LMG to be fired from the shoulder. Existing stocks were modified to the new standard which involved loss of the cooling shroud and radiator (if affixed), addition of a forward hand grip (as well as hand guard), installation of a muzzle compensator and use of a traditional rifle-style butt.
Back in 1940, the American firearms concern of Savage Arms Corporation took on production of the Lewis Gun in .30-06 Springfield caliber and this form was recognized by the British as "Savage-Lewis" guns to avoid confusion with their existing .303 British machine gun stocks. A red, two-inch band was also painted on these British models to clearly differentiate their chambering to unsuspecting users. Early forms incorporated a wooden butt but these later gave way to a cheaper metal skeleton type arrangement. Original sighting devices were also fixed while later models showcased adjustable types ranged to 400 yards. Grips were of the spade type. The British Navy procured some of this form throughout the year and these were later passed on to British Home Guard units.
In the post-war years, the Lewis Gun continued service as the Mark 4 was adopted on August 16th, 1946. The Mark 4 involved existing Mark 3 guns revised to an easier mass-production standard. Earlier Mark 1 guns were to be updated to the Mark 4 standard under the Mark 1* designation but it is believed that none ever saw the light of day for the Mark 1, itself, was officially labeled "obsolete" by British authorities. Ironically, the declaration was made on the same day of adoption of the Mark 4 in 1946.
From this point forward, Lewis Guns began to fall largely out of use for, by 1953, they were mostly out of frontline circulation in any one army. Production spanned from 1913 to 1942 with use beginning as far back as 1914. Despite its formal retirement, the Lewis Gun has appeared in more modern conflicts as was the case during the Arab-Israeli War (1948-1949), "The Troubles" (Northern Ireland, 1960-1998) and during the Croatian War of Indepedence (1991-1995).
The Lewis Gun was officially adopted by the forces of Australia, Belgium, Canada, Czechoslovakia, Japan, Estonia, Finland, France, Honduras, Ireland, Italy, Israel, Mexico, Netherlands, Newfoundland, New Zealand, Nicaragua, Norway, Philippines, Poland, Portugal, the Russian Empire (and, later, the Soviet Union), Taiwan, the United Kingdom, the United States and Yugoslavia. The German Empire of World War 1 and the Nazi German regime of World War 2 both used presumably captured stocks and chambered them for local 7.92mm cartridge. Captured Lewis Guns in German service were bestowed the designation of MG 137(e).