The SKS is a Russian 7.62x39mm caliber semi-automatic carbine, designed in 1945 by Sergei Gavrilovich Simonov. SKS is an acronym for Samozaryadniy Karabin sistemi Simonova (Russian: Самозарядный карабин системы Симонова), 1945 (Self-loading Carbine, Simonov's system, 1945), or SKS 45. The SKS carbine was rather quickly phased out of first-line service, replaced by the AK-47, but remained in second-line service for decades afterwards. It remains a ceremonial arm today. It was widely exported and produced by the former Eastern Bloc nations, as well as China, where it was designated the "Type 56", East Germany as the "Karabiner S" and in North Korea as the "Type 63". It is today popular on the civilian surplus market in many countries. Together with the RPD light machine gun the SKS was one of the first weapons chambered for the 7.62x39mm M43 round later used in the AK-47 and RPK.
A standard SKS is semi-automatic and has a fixed/hinged 10 round magazine which is loaded from the top of the rifle either by manually inserting the ammunition one round at a time or with a 10-round stripper clip. In typical military use, the stripper clips are disposable, although they may actually be reloaded many, many times and reused if necessary. The SKS is a gas-operated weapon that has a spring-loaded operating rod and a gas piston rod that work the action via gas pressure pushing against them. Also, it has a "tilting bolt" action locking system. Some variants of the SKS have been modified, with limited success, to accept AK-47 detachable magazines (military rifles designed with fixed magazines often experience feed jams when modified to accept detachable magazines, and the SKS is no exception). Norinco had, at one point, manufactured the SKS-M, SKS-D, and MC-5D models which were engineered from the factory to accept AKM magazines without problems (though the wood stock must be relieved to accept drum magazines). The SKS also has a slightly longer barrel than AK-series rifles, with a fractionally higher muzzle velocity.
While early Russian models had spring-loaded firing pins, most variants of the SKS have a free floating firing pin within the bolt. Because of this design, care must be taken during cleaning (especially after long storage) to ensure that the firing pin does not stick in the forward position within the bolt. SKS firing pins that are stuck in the forward position have been known to cause accidental "slamfires" (uncontrolled automatic fire that empties the magazine, starting when the bolt is released). This behavior is less likely with the hard primer military-spec ammo for which the SKS was designed, but as with any rifle the user should properly maintain his firearm. For collectors, slamfires are more likely when the bolt still has remnants of cosmoline embedded in it. The firing pin is triangular in cross section, and slamfires can also result if the firing pin is inserted upside down.
In most variants (Yugoslav models being the most notable exception), the barrel is chrome lined for increased wear and heat tolerance from sustained fire and to resist corrosion from chlorate primed corrosive ammunition, as well as to facilitate cleaning. Chrome bore lining is common in military rifles. Although it can diminish practical accuracy, this is not a real limit on field grade accuracy in a weapon of this type.
All military SKSs have a bayonet attached to the underside of the barrel, which is extended and retracted via a spring-loaded hinge (some are removable whereas some are permanent). The SKS is easily field stripped and reassembled with no tools. The rifle has a cleaning kit stored in a trapdoor in the buttstock, with a cleaning rod running under the barrel, in the same style as the AK-47. In common with other Soviet-era designs, the SKS trades accuracy for ruggedness, ease of maintenance, ease of use, and low manufacturing cost. The SKS is a simple design that is highly effective and rugged.
During World War II, many countries realized that existing rifles, such as the Mosin-Nagant, were too long and heavy and fired overly powerful cartridges, creating excessive recoil. These cartridges, such as the 7.92x57mm Mauser, .303 British, .30-06 Springfield, and 7.62 x 54R were effective to ranges of up to 2,000 meters (2,200 yd); however, it was noted that most firefights took place at maximum ranges of between 100 meters (110 yd) and 300 meters (330 yd). Both the Soviet Union and Germany realized this and designed new weapons for smaller, intermediate-power cartridges. The German approach was the production of a series of intermediate cartridges and rifles in the interwar period, eventually developing the Maschinenkarabiner, or machine-carbine, which later evolved into the MP44 Sturmgewehr, or "assault rifle", which was produced during the war, chambered in the 7.92x33mm Kurz intermediate round.
Design-wise, the SKS relies on the AVS-36 (developed by same designer) to a point that some consider it a shortened AVS-36, stripped of select-fire capability and rechambered for the 7.62x39mm cartridge. It also owes heavily to the earlier SVT-40 and M-44 Mosin-Nagant rifles that it replaced, incorporating both the semiautomatic firepower of the SVT (albeit in a more manageable cartridge) and the small, fast-handling size and integral bayonet of the bolt-action carbine.
In 1949, the SKS was officially adopted into the Soviet Army, produced at the Tula Armory from 1949 until 1955 and the Izhevsk Armory in 1953 and 1954. Although the quality of Russian SKS rifles manufactured at these state-run arsenals was quite high, its design was already obsolete compared to the Kalashnikov which was selective-fire, lighter, had three times the magazine capacity, and had the potential to be less labor-intensive to manufacture. Gradually over the next few years, AK-47 production increased until the extant SKS carbines in service were relegated primarily to non-infantry and to second-line troops. They remained in service in this fashion even as late as the 1980s, and possibly the early 1990s. To this day, the SKS carbine is used by some ceremonial Russian honor guards; it is far less ubiquitous than the AK-47 but both original Russian SKS rifles and copies can still be found today in civilian hands as well as in the hands of third-world militias and insurgent groups.
The SKS was to be a gap-filling firearm produced using the proven operating mechanism design of the PTRS and using proven milled forging manufacturing techniques. This was to provide a fallback for the radically new and experimental design of the AK-47, in the event that the AK were to prove a failure. In fact, the original stamped receiver AK-47 had to be quickly redesigned to use a milled receiver which delayed production, and extended the SKS rifles' service life.
During the Cold War, Russia shared the design and manufacturing details with its allies. Therefore, many variants of the SKS exist. Some variants use a 30-round AK-47 style magazine (Chinese Type 68 and 68/72, also known as "D" & "M" models), gas port controls, flip-up night sights, and prominent, muzzle-mounted grenade launchers (Yugoslav M59/66, possibly North Korean Type 63). In total, SKS rifles were manufactured by Russia, China, Yugoslavia, Albania, North Korea, Vietnam, and East Germany (Kar. S) with limited pilot production (Model 56) in Romania and Poland (Wz49.) Physically, all are very similar, although the NATO-specification 22 mm grenade launcher of the Yugoslav version, and the more encompassing stock of the Albanian version are visually distinctive. Early versions of the Russian SKS and later Chinese Type 56s (produced 1965-71) used a spike bayonet, whereas the majority use a vertically-aligned blade. Many smaller parts, most notably the sights and charging handles, were unique to different national production runs. A small quantity of SKS carbines manufactured in 1955-56 were produced in China with Russian parts, presumably as part of a technology sharing arrangement. Many Yugoslav M59/66 series rifles were exported to Uruguay and Mozambique; the Mozambique versions having teakwood stocks, the wood supplied by that nation. The vast majority of Yugoslav M59 and M59/66s have elm, walnut and beech stocks. SKS carbines have also made appearances in recent conflicts in Africa, Afghanistan, and Iraq.
Nations that utilized the SKS but did not receive manufacturing rights included Afghanistan,Congo, Indonesia, Iraq, Laos, Lebanon, Mongolia, Morocco, the United Arab Republic (Egypt) and the Yemen People's Democratic Republic.
The SKS has also been featured prominently around the world during times of civil unrest. In the United States, the SKS was used successfully by Korean shopkeepers to fend off looters during the 1992 Los Angeles riots.
After World War II, the SKS design was licensed or sold to a number of the Soviet Union's allies, including China, Yugoslavia, Albania, North Korea, Vietnam, East Germany, Romania and Poland. Most of these nations produced nearly identical variants, with the most common modifications being differing styles of bayonets and the 22 mm grenade launcher commonly seen on Yugoslavian models.
NOTE: All SKS variants except for the Yugoslav M59/66 are carbines. This is due to the additional length that the flash hider/grenade launcher attachment gives to the SKS.
Differences from the "baseline" late Russian Tula Armory/Izhevsk Armory SKS:
There is some debate as to the relative quality of each nation's SKS production; Yugoslav types are generally considered to be better made than Chinese, yet the Chinese types typically have chrome lined barrels while the Yugoslav versions do not. East German, Russian and Albanian SKSs bring a higher price than those of other countries, the stock on the Albanian versions being of a slightly different manufacture and being rarer due to low production numbers. There were approximately 18,000 Albanian SKSs manufactured during the late 1960s until 1978, and of those, approximately half were destroyed. Most of the remaining East German SKSs had been sold/transferred to Croatia in the early 1990s.
A sporterized hunting version of the SKS is still manufactured in Serbia, by the Zastava Armory. It is designated the LKP 66, and features a "Monte Carlo" style one-piece stock, receiver mounted scope mount, modified trigger, and flush-fit 7 round magazine. It also has a redesigned front sight with no bayonet mount.
The SKS is popular on the civilian surplus market, especially in the United States. Because of their historic and novel nature, Russian and European SKS rifles are classified by the BATF as "Curio & Relic" items under US law, allowing them to be sold with features that might otherwise be restricted. Chinese manufactured rifles, however, are not so classified. Because of the massive size of the Chinese People's Liberation Army, over 8 million Chinese SKS rifles were produced during their 20 years of use making the Chinese SKS one of the most mass produced military rifles of all time.
In Australia, the Chinese SKS rifle (along with the Russian SKS rifle) was very popular with recreational hunters and target shooters during the 1980's and early 1990's before semi-automatic rifles were banned from legal ownership in 1996. Since the introduction of the 1996 gun bans in Australia, the Mosin-Nagant series of bolt-action rifles and carbines have now filled the void created by politicians when the SKS was banned from legal ownership.
In the early 1990s, the Chinese SKS rapidly became the "poor man's deer rifle" in some Southern areas of the United States due to its low price, lower even than such old favorites in that role as the Marlin 336. Importation of the Chinese SKS into the USA was banned in 1994.
Due to its relatively low cost and widespread availability and usage, the SKS has spawned a growing market for both replacement parts and accessories. Many aftermarket parts are available to upgrade the rifle — sometimes so considerably that it bears little resemblance to the original firearm. This process, known as "sporterizing" (or by the somewhat derogatory terms "bubba'd or "tapcofucked"), may include items such as synthetic buttstocks, extra capacity magazines, replacement receiver covers (which allow the mounting of scopes, lasers, etc.), different muzzle brakes, recoil buffers, and more.