The Mondragon Rifle became one of the first semi-automatic service rifles to be adopted in quantity by a major military force as well as one of the first to see combat service anywhere in the world - this during a period when the standard service rifle was a manually-actuated bolt-action long gun. The rifle received its name from its designer - Manual Mondragon (1859-1952), a general serving in the Mexican Army from 1880-1914. Mondragon began work on a new automatic rifle concept in 1882 and was granted its patent in 1887. The weapon would go into see combat action in the Mexican Revolution (1910-1920), World War 1 (1914-1918), the 2nd Sino-Japanese War (1937-1945), World War 2 (1939-1945), the Ecuadorian-Peruvian War (1941), the Chinese Civil War (1927-1950), the Korean War (1950-1953), and the Vietnam War (1955-1975).
The driving principle behind the revolutionary Mondragon Rifle was its use of a gas-cylinder operation (tapped from the barrel) which drove a piston and featured a rotating bolt with locking lugs and a grooved receiver. Such a design was ahead of its time in a world where trust was still placed in the proven yet cumbersome manual bolt-action. Another unique facet of the rifle - and this instilled into its design by governing authorities who mistrusted such automated mechanical functions in weaponry - was that the automatic system could be disconnected from the bolt and allow the rifle to be fired as a standard, "straight-pull" bolt-action weapon. The Mondragon Rifle was chambered to fire the 7x57mm Spanish Mauser cartridge to which the base rifle was produced with an eight round box magazine.
Production of the Mondragon Rifle began in 1887 to which some 1,175,400 examples would be ultimately produced. However, early versions were produced overseas as local Mexican factories lacked the ability to manufacturer such a complex weapon and little interest was shown in the neighboring United States. As such, the Swiss firm of Schweizerische Industrie Gesellschaft firm of Switzerland (better known today by its initials of "SIG"), received an initial contract for or some 4,000 production rifles. Deliveries began soon after with the first rifles arriving in Mexico in 1901 under the Mexican Army designation of "Fusil Mondragon Modelo 1900".
Once in practice, the Mondragon Rifle showcased the quality standards common to Swiss-made arms and Mondragon's engineering prowess shown through. The weapon proved a very capable and powerful man-stopper and the automated repeating action was a very advanced concept for a rifle in this period. However, the system as a whole proved rather unwieldy during full-automatic fire no thanks to the inherently violent recoil (common to many early repeating rifles) and, as such, accuracy in this mode was rather poor at distance.
The Mondragon Rifle line was broadened with the development of a light machine gun model. This version introduced a bipod for forward support as well as higher magazine counts (30- and 100-round drums became available). As a light machine gun, the type could be used to suppress enemy movements or assist as a portable infantry squad support light machine gun similar to today's FN Minimi model. The Mondragon Light Machine Gun (LMG) served in this role with the Mexican Army until it was replaced by the Mendoza M1943 General Purpose Machine Gun (GPMG) of 1943.
It was not until 1908 that Mexican factories were retooled and ready to produce the rifle as a local product. The wholly Mexican-produced rifles were now designated as the "Fusil Porfirio Diaz Sistema Mondragon Modelo 1908". The key differentiating feature with these models was in their standard 20-round shot capacity. Further production plants came online thereafter and manufacture of the indigenous weapon spanned up until the middle of the Second World War in 1943.
The Mexican Revolution (1910-1920) changed several homefront factors across the country. By 1911, the movement keen on removing then-President Diaz and only 400 Mondragon Rifles had been delivered to this point from the initial production order. The subsequent governmental upheaval cancelled the Mexican-SIG contract concerning the Mondragon Rifle. This left SIG with the remaining portion of the 4,000-strong Mondragon order with no buyers. SIG did manage to sell off several hundred of the type to interested parties around the globe and the authorities of the German Empire eventually procured the remaining 3,000 rifles in 1914 - the beginning of World War 1.
These German-own Mondragon Rifles were issued to both infantrymen and aviators and some were passed to the Austro-Hungarian Empire. In the former role, the rifle proved too prone to collecting environmental debris that resulted in frequent jamming. As such, the rifles were eventually removed from frontline service. In the latter role, the weapons were fitted with 30-round helical magazines and designated as the "Fliegerselbstladekarabine Modell 1915" (literally meaning "Pilot's Self-Loading Carbine Model 1915") and issued to scout fighter planes to help off-set the limited supplies of German aerial machine guns. However, once production of machine guns kept up with relative demand, the Mondragon as an aerial implement was altogether dropped. Some Mondragon Rifles were further issued to elements of the German Navy and saw service up until the end of the war in 1918.
After the war, Mondragon supply dictated that Mexican authorities try to sell their unique rifle on the open global market. Customers ultimately ranged from all over the world including both local allies and friendly nations as well as those parties willing to pay for local-license production rights. Post-war and inter-war Germany, the Japanese Empire and Austria all elected to produce the rifle at home. Production was such that the rifle was available in some numbers by the start of World War 2 and some even were fitted with optic sights for the specialized sniper role. Mexico directly supplied their Mondragon Rifles to guerilla forces in the Philippines to stave off the invading Japanese Army. Vichy French forces also fielded the rifle for a time as did the forces of China and the Soviet Union.
The Mondragon saw future actions in several other limited and wide-ranging conflicts including the Korean War and the Vietnam War.
Mexico utilized the Mondragon family line of firearms in some form or another up until 1949. Some foreign operators continue to use the type even today.