The story of the first semi-automatic rifle ever widely-adopted as a standard military arm began after the start of the First World War, when the inventor John C. Garand (Canadian, then living in USA) began to develop a semi-automatic (or self-loading) rifles. He worked at the government-owned Springfield armory and during the 1920s and early 1930 developed a number of design. Early rifles were built using somewhat rare system of the cartridge primer blowback, but due to some reasons this system was unsuitable for a military rifle, so he switched to the more common gas-operated system. He filed a patent for his semiautomatic, gas operated, clip-fed rifle in 1930, and received an US patent for his design late in 1932. This rifle was built around then-experimental .276 caliber (7mm) cartridge. At the same time, his rifle was tested by the US Military against its main competitor, a .276 caliber Pedersen rifle, and was eventually recommended for adoption by US Army early in the 1932. But a little bit later an US general MacArthur stated that the US Military should stick to the old .30-06 cartridge. Foreseeing that, Garand already had a variation of his design chambered for 30-06. Finally, at the 6th January, 1936, the Garands' rifle was adopted by the US Army as an "rifle, .30 caliber, M1". Early issue rifles, however, showed a quite poor characteristics, jamming way too often for a decent military arm, so a lot of noise was raised that eventually reached the US Congress. In the 1939, the major redesign was ordered, and Garand quickly redesigned a gas port system, which greatly improved the reliability. Almost all M1 rifles of the early issue were quickly rebuilt to adopt a new gas system, so very few "original" M1 Garand rifles survived to present days, and those are extremely expensive collectors items. When the USA entered the World War 2, the mass production of the M1 rifles was set at the Springfield armory and at the Winchester. During the war, both companies developed about 4 millions of M1 rifles, so M1 Garand is a most widely used semi-automatic rifle of the World War 2. During the war, M1 Garand proved itself as a reliable and powerful weapon. There were minor attempts to improve it during the war, but these did not left experimental stages, except for two sniper modifications, M1C and M1D. Both were approved for service in the 1945 and both featured a telescope sight which was off-set to the left due to the top-loading feature of the M1. After the end of the WW2 the production of the M1 in the USA was stopped, and some rifles and also licenses to built it were sold to other countries, such as Italy and Denmark. With the outbreak of the Korean war in 1950 the production of theM1 for US forces was resumed early in 1952. Rifles were manufactured at Springfield armory, and also at Harrington & Richardson Company (H&R) and International Harvester Company. Those companies manufactured M1s until the 1955, and Springfield Armory produced the Garands until 1956. With the official adoption of the new rifle and ammunition in 1957, M14 and 7.62x51mm NATO, respectively, for US service, the M1 rifle became obsolete. It was still used during the later years, however, due to the lack of M14 and M16 rifles, and saw some service during the early period of the Vietnam war. Later, many M1s were transferred to the US National Guard, used as a training weapons by US Army or sold to civilians as a military surplus. Few M1 are still used by all branches of the US Military as a ceremonial weapons. Other than USA, M1s were used by Italy (where these rifles were lately redesigned and rebuilt into 7.62mm BM-59 rifles). Denmark, France and some other countries. There also were attempts to rebarrel the M1 for 7.62mm cartridge in the USA and to adopt a detachable 20-rounds magazines from Browning BAR rifles, but these were less than successful and haven't seen any significant service.
M1 is a gas operated, magazine fed, semiautomatic rifle. Original M1 were using the gas, that was tapped from muzzle by the special muzzle extension, but this was proven unreliable, and since the 1939, M1 rifles were built with gas system that used a gas port, drilled in the barrel near the muzzle. The tapped gas was directed into the gas cylinder, located under the barrel, where it operated a long-stroke gas piston, integral with the operating rod. Long operating rod housed inside it a return spring, and ended with the extension, that carried a bolt operating groove at the left and a charging handle at the right. The groove was connected with the rotating bolt, located inside the receiver. Bolt had two locking lugs that locked into the receiver walls. When gun was fired, hot powder gases were led to the gas chamber and to the gas piston, that drove back the operating rod. The bolt operating grove, interacting with the stud on the bolt, rotated bolt to unlock it and then retracted it to commence the reloading cycle.
M1 was fed from the integral box magazine, which was probably the weakest point of the whole design. The magazine was fed using only the 8-rounds clips, which stayed inside the magazine until all 8 rounds were shot. As soon as the magazine (and clip) became empty, bolt was stopped at its rearward position by the bolt catch, and the empty clip was automatically ejected from the magazine with the distinctive sound. The main drawback of the system was that the clips could not be easily reloaded during the action. However, there still was the possibility to refill the clip in the rifle, but this was not the fastest procedure.
M1 featured a wooden stock with separate handguards and a steel buttplate. The forwardmost part of the muzzle served as a bayonet mounting point. Sights of the M1 consisted of the front sight with dual protecting "wings", dovetailed into the gas block at the muzzle, and the adjustable peephole rear sights, built into the rear part of the receiver. Sniper versions (M1C and M1D) also featured scope mounts on the receiver, offset to the left from the axis of the rifle, so it was possible to load it with clips and also to use its iron sights with scope installed (in the case of the scope damage, for example).
There were some attempts to make a handier and more compact version of the M1 by shortening the barrel by some 6 inches (152 mm), with standard wooden or skeleton metallic buttstocks, but these attempts never left the experimental stages. Some short barreled "tankers" M1 rifles, appeared in the post-war period, are not the genuine designs, but the "sawed-off" variations of the standard "long" rifles.