Evolution of the Kalashnikov rifle
Mikhail Kalashnikov, the designer of the AK, started designing firearms in 1941. M. Kalashnikov was wounded after a shot in his shoulder during the battle of Bryansk, and was hospitalized, a soldier next to him said: 'Why do our soldiers have only one rifle for two or three of our men, when the Germans have automatics?'
Kalashnikov designed a sub-machine gun in 1942 and machine gun in 1943. In 1944, the USSR was looking for a new family of small arms chambered in the 7.62x39mm (M43) intermediate cartridge, and Kalashnikov received a batch to start designing a new rifle. His first rifle in the M43 cartridige came out in 1944 and was heavily influenced by the American M1 garand, using a similair type of action. Kalashnikovs rifle lost against simonovs rifle, the SKS.
In 1946, there was another competition for a rifle, but more for like a sub-machine gun/carbine role. Kalashnikov created a new rifle, the AK-46, where the gas system is above the barrel, 2 part receiver, seperate trigger housing and left side non reciprocating charging handle. in november 1947, a new prototype was completed. A single part receiver, a single selector lever which also acts as a dust cover for the charging handle slot and in general a simplier rifle. The AK-47 was born.
In 1949, Kalashnikovs rifle was officially adopted as the 7.62 mm Kalashnikov rifle (AK)
AK types:
AK Type 1: Original stamped receiver rifle.
Ak Type 2: Milled receiver rifle, production from 1951-1957
Ak Type 3: finalized milled receiver rifle: produced since 1955, the Type 3 was also produced abroad by other Warsaw pact nations
Ak Type 4: The AKM, stamped receiver modernized rifle, went into production in 1959 and the most common AK variant.
The AK74
In the 1960's, the USSR was developing a new smaller caliber cartridge to compete with the 5.56x45mm Nato. The cartridge was developed for the following reasons, a lighterweight round so troops are able to carry more, it is more controlable for automatic fire and easier to shoot follow up shots and overall better ballistics. The USSR developed the 5.45x39mm round, and now they needed a new family of small arms. After trials, the AK74 was chosen.
The AK74's operating mechanism is the same as the original AK, but none of the parts are interchangable. It still remains it stamped receiver construction. The AK74 is chambered in 5.45x39mm and uses Ag4s (not bakelite) magazines as the standard magazine (the AKM used both Ag4s and steel magazines), it featured a new muzzle break, different wood furniture and smaller improvements. The AKS74 used a new side folding stock instead of the Ak underfolding stock. Around the 1980's, the Ak74's were produced with fiberglass reinforced plastic furniture.
AK74 variants:
AK74: Rifle
AK74N: Rifle with side rail mount
AKS74: Folding stock
AKS74N: Folding stock with side rail mount
AKS74U: Compact assault rifle variant
The AK74M and Ak100 series
In 1991, full scale production of the AK74M started, the AK74M is the modernized version of the Ak74, it featured new black plastic furniture, a folding plastic stock a side rail from the AK74N and again smaller improvements.
The AK100 series was introduced in 1994 as a new family of Kalashnikov rifles based of the AK74M. The AK100's were produced with interchangable parts to simplify production.
AK100 variants:
AK101: 5.56x45mm rifle
AK102: 5.56x45mm carbine
AK103: 7.62x39mm rifle
AK104: 7.62x39mm carbine
AK105: 5.45x39mm carbine
AK107: 5.45x39mm rifle with balanced recoil system
AK108: 5.56x45mm rifle with balanced recoil system
The AK12 and AK400 series
The AK12 is the latest Kalashnikov rifle. The AK12 is mechanically also the same as the original AK and chambered in 5.45x39mm, but the early AK12 variant had 2 round burst option. The AK12 has a new gas tube construction, a railed dustcover, free float railed handguard, selector lever with finger extension, foldable and collapsible stock and a aperture rear sight. There were many AK12 prototypes and the final AK12 prototype was based of the AK400 series and it was introduced in 2016. The AK12 was officialy adopted in 2019.
In 2021, a new variant of the AK12 came out with a new stock and pistol grip assembly, and the 2 round burst option was removed.
The AK12 seems to have alot of issues, the railed dustcover does not hold zero and so does the handguard, the new gas tube construction makes it harder to clean so alot of carbon builds up in spots which are near impossible to clean, ugly weld on the receiver where the gas tube is fixed to, selector lever which overrides and corrosion problems.
AK400 variants:
AK12: 5.45x39mm rifle
AK15: 7.62x39mm rifle
AK19: 5.45x39mm rifle
AK308: 7.62x51mm rifle