One of the most derided guns in military history - the French "Chauchat" light machine gun - received its start in the fighting of World War 1. However, there proved two sides to the Chauchat story for the French versions chambered in their original 8mm cartridges were well-regarded, useful battlefield weapons - even the Belgian forms in their 7.65x53mm Argentine Mauser chambering fared fairly well without notable issues. On the other side was the American-modified form - the M1918 - chambered for the more powerful 30-06 cartridge which played extremely poorly with the fragile, lightweight Chauchat design. Indeed, American fighters operating Chauchats in 8mm Lebel caliber found success with this weapon and several became decorated veterans of the war while engaging the enemy with their Chauchat Light Machine Guns.
The Chauchat design stemmed from early-century work by a committee of French personnel that included Colonel Louis Chauchat. The designed direction led to a gun that could be transported by one man into battle, supplied machine-gun-level firepower, and could be mass-produced through limited manufacturing facilities. When France entered World War 1 in August of 1914, it lacked a light machine gun weapon and thusly the Chauchat was taken into production during September as the "Fusil Mitraileur CSRG Modele 1915".
From the outset, the Chauchat was intended for large-scale production using minimal machinery and this meant that the design took on an overall crude appearance. The action was all contained inline which theoretically supported accuracy. Its general arrangement involved a central tube form making up the receiver and barrel with iron sights fitted over the mass of the weapon and a forward fixture aft of the muzzle. The muzzle itself was capped by a conical flash suppressor. A simple wooden rifle-style shoulder stock was fixed into the rear of the receiver with an even simpler pistol grip fashioned under it. A forward, knobbed grip was set just ahead of the primary grip with the magazine well featured just ahead of this appendage. A thin, wiry folding bipod was used to balance the weapon against terrain as a forward support when firing.
The magazine was of a peculiar, semi-circle shape, forced upon it by designed due to the tapering nature of the French 8x51mm Lebel rifle rimmed cartridge. This arrangement allowed for 20 x 8mm cartridges to be fitted into the spring-loaded, metallic detachable box magazine. Two side ports cut into the magazine sides allowed the operator to instantly read the ammunition count. Spent shell casings were ejected from a port along the center-top portion of the weapon.
In addition to production expediency, the Chauchat was purposefully designed as a lightweight, transportable weapon at a time when machine guns were large, heavy systems typically arranged as stationary defensive emplacements. Portability allowed the Chauchat operator to bring machine gun firepower directly to the enemy, clearing out trenches faster than any bolt-action service rifle could manage. The weapon featured a muzzle velocity of 1,970 feet per second and a rate-of-fire of 240 rounds per minute for the role. Overall length was 46 inches with a weight of 23lbs when loaded with a 20-round magazine.
The Chauchat's action centered around a gas-assisted "long-recoil" operation which entailed the bolt and barrel moving rearwards in unison (the full length of the cartridge) to complete the firing cycle (known as "full stroke"). The bolt was then locked while the barrel returned forward and this motion led to a fresh cartridge being stripped from the awaiting magazine. Once the barrel and bolt were fully set back in place, the action was completed and the weapon ready to cycle again.
Manufacture of the weapon was handed to "Etablissements des Cycles Clement-Galdiator" of Paris, a well-known French bicycle-maker who specialized in tubular metal forming. As such, the cheap and light gun's construction revolved around drawn tubing and sheet steel. Some 244,000 were made to the 8mm Lebel chambering and quickly issued to French Army forces. In practice, these weapons largely well accepted and its history of troubles were not as persistent as that as seen in American Army usage (detailed below). The Chauchat went on to become one of the most-produced small arms of World War 1 - total production reaching 262,000 examples by the end. French colonial security forces used the type in Morocco until 1932.
This is not to say that Chauchats were without faults - indeed the design held several inherent flaws about her. To begin with, the weapon was mass-produced by a company with little experience in the manufacture of firearms which led to inferior parts, quality control, and poor construction practices being implemented. This, in turn, could lead to breakages in the heat-of-battle. The long-recoil action made the weapon inaccurate in untrained hands, testing indicating that only the first shot had any chance of reasonable success when hitting a defined target: as such a strong, two-handed grip was required when firing the weapon. Additionally, the exposed cartridges within the cut-out magazines held the propensity to collect all manner of battlefield debris - dust, dirt, and mud - common to World War 1 battlefields, leading to a fouling of the feeding action under certain conditions. The sharply-tapered magazine design also led to noted stoppages.
Beyond its French use, neighboring Belgium took on a stock of 6,935 Chauchats and roughly half were rechambered for the 7.65x53mm Argentine Mauser cartridge. These also reportedly gave good service under wartime conditions. Finland received 5,000, Greece 3,980 units, Italy 1,729, and Romania about 7,200 examples. The Russian Empire secured about 6,100 of the weapon and these persevered in service during the Russian Civil War years under the command of Red Army units. Serbia managed a stock of 3,838 of the machine guns and Poland received up to 11,869 to which roughly half were rechambered for 8mm Mauser. Some were then delivered to Spain for use in the Spanish Civil War (1936-1939).
When the United States Army arrived in support of the Allies during the fighting of 1917, Army authorities secured several French automatic weapons to shore up shortages in their own inventory. One of the weapons became the Chauchat Light Machine Gun recognized as "Automatic Rifle, Model 1915 (Chauchat)" and nicknamed "Sho-Sho" by American Doughboys. These were adopted under the designation of "Model 1918" ("M1918") to which some 13,000 to 16,000 of the French guns were passed to the Americans, still chambered for the original local 8mm French Lebel rifle cartridge. To make better use of the more familiar 30-60 Springfield cartridge for American troops, it was decided to rechamber the weapon and feed from a new, straight-box detachable magazine design.
These changes begat the oft-publicized terrible operational history of the Chauchat - primarily due to the 30-06's greater inherent power which pushed the Chauchat internal components to their absolute limited. Breakages were common as were stoppages. An order for 25,000 of the weapon became about 19,000 practical forms and several thousand were eventually relegated to training duties as quickly as a replacement could be found. This eventually came in the form of the storied Browning M1918 "BAR" ("Browning Automatic Rifle") - a twenty-shot, magazine-fed light machine gun from famed American gunsmith John Moses Browning that would go on to see far more combat service in World War 2 than the current global conflict. However, the BARs did not arrive in serviceable numbers by the end of the war, issuance beginning about September of 1918 - the war in Europe would be over with the Armistice of November 1918. By this time, the French only held about 63,000 Chauchats in their own inventory.