Kalashnikov AK-47, AK assault rifle (USSR)

The Avtomat Kalashnikov AK (автомат Калашникова), colloquially known in the West as the Kalashnikov AK-47, was one of the results of Soviet intermediate cartridge program. This program commenced in mid-1943, after close examination of the captured German MKb.42(H) assault rifle and US M1 carbine, supplied through the Lend-lease. Soviet experts found the idea of an intermediate cartridge to be highly promising and assigned the task to create an indigenous medium-power round to the OKB-44. The first versions of the new cartridge appeared in late 1943. This round featured a rimless bottlenecked steel case 41mm long, loaded with a lead-cored jacketed bullet weighing 8 grams. Later on, circa 1945-46, the case was shortened to 39mm with the introduction of the longer, boat-tailed bullet with a mild steel core.

 

diagram of the original 7.62mm M1943 cartridge, with 41mm case
diagram of the original 7.62mm M1943 cartridge, with 41mm case

 

With the cartridge ready, the General Artillery Department of the Red Army (GAU) initiated several R&D programs to produce new weapons. Unlike Germans, Soviet experts wanted a complete small arms system built around the same intermediate round. This system should include a semi-automatic carbine as a primary infantry weapon, an automatic assault rifle (“Avtomat” in Russian terminology) to replace pistol-caliber submachine guns and a squad automatic weapon / light machine gun.
Carbines and light machine guns were tested separately, and these parts of the program resulted in the adoption of the Simonov SKS carbine and Degtyarov RPD machine gun  in 1949. The “Avtomat” trials commenced in late 1944. The early forerunner in these trials was the Sudaev AS-44, which was extensively tested in the field during mid-1945. However, it was decided to continue development using modified requirements, which stemmed from field tests of the AS-44. There were numerous contenders in the trials of 1946, including the young and aspiring Mikhail Kalashnikov, a former tank corps sergeant, who worked at the Scientific and Research Small Arms Proving Ground at Schurowo as an apprentice arms designer since late 1942.

By 1946 Kalashnikov already have designed several experimental weapons, including a submachine gun (1942), light machine gun (1943), semi-automatic carbine (1945), plus a number of useful improvements for the Goryunov SGM machine gun. For trials of 1946 Kalashnikov submitted three experimental weapons, known as AK-46. Those featured short-stroke gas systems, rotating bolt locking, separate upper and lower receiver connected by cross-pins, and left side controls with separate safety and selector levers.

 

Kalashnikov AK-46 experimental assault rifle
Kalashnikov AK-46 experimental assault rifle

 

Kalashnikov AK-46 experimental assault rifle
Kalashnikov AK-46 experimental assault rifle, disassembled

 

No contenders were successful in this round of trials, and three designers were allowed to update their prototypes for the next round of trials, scheduled for late 1947. Those were Kalashnikov, Bulkin, and Dementiev.
Following recommendations from the trials comission and also using a good deal of advanced thinking, Kalashnikov and his aide Zaitsev have redesigned their rifle, which now used several features reminiscent of the Bulking assault rifle, including the shape of the receiver and its cover, long-stroke gas piston attached to the bolt carrier, etc. As a result of these upgrades, Kalashnikov AK successfully won the trials in December of 1947, proving to be much more reliable and durable than its rivals. It was recommended for a limited series production and field trials, which happened in 1948. By that time the Kalashnikov Avtomat was designated as AK-47. However, upon its official adoption in 1949, it was christened simply as Avtomat Kalashnikova AK, although the “AK-47” name was used from time to time in various correspondence and documents for several years afterwards.

 

Kalashnikov AK-47 experimental assault rifle
Kalashnikov AK-47 experimental assault rifle, photo from trials report of 1947

 

Kalashnikov AK-47 experimental assault rifle, photo from trials report of 1947
Kalashnikov AK-47 experimental assault rifle disassembled, photo from trials report of 1947

 

Kalashnikov AK-47 experimental assault rifle with folding stock
Kalashnikov AK-47 experimental assault rifle with folding stock

 

Kalashnikov AK-47 assault rifle, made in 1948 for field trials
Kalashnikov AK-47 assault rifle, made in 1948 for field trials

 

cover of the AK-47 manual, dated 1949
cover of the AK-47 manual, dated 1949

 

Mass production of the AK was ordered to Izhevsk Machine building factory No.74, also known as IZHMASH.

A brief note must be made about the small team of German engineers (15 men total, including Horn, Gruner, Schmeisser, Schink, etc) that were working in Izhevsk between 1946 and 1951. Those people had zero relations to the design of the AK-47, as all design work was conducted by Kalashnikov in the city of Kovrov, at the factory no.2. When Kalashnikov moved to the Izhevsk in 1948, he already had his design mostly completed. Furthermore, German designers were expressly prohibited from access to anything classified as secret, and back in 1948-50 the AK was deemed to be a “secret development”.

The first mass-produced Avtomat Kalashnikova AK featured a stamped steel receiver, same as the experimental AK-47, and several minor changes, including the omission of an ineffective muzzle compensator. In the West, this version is unofficially called “AK Type 1”. However, by the end of 1949, it became clear that stamped receivers with welded bolt rails and pinned trunnions is too complex and results in an excessive rate of rejected receivers. To solve this problem, Kalashnikov developed a machined steel receiver, which, while requiring more raw metal, allowed to save significant time and effort on assembly, quality checks, and “unbending” of warped or deformed stamped receivers. This version was approved for production in 1950 and entered mass manufacture in 1951. Known in the West as “AK Type 2”, this machined receiver variant remained in production through 1955, when it was replaced by the “Lightened AK”. This third version also featured a machined receiver, but thanks to various cuts and modifications weighed about 0.5 kg less than its predecessor. Known in the West as “AK Type 3”, lightened AK remained in production until 1959 when it was finally replaced with a new, stamped steel receiver “AK Modernized”, or AKM in short.

 

The first and original Kalashnikov AK-47 set the general pattern for all subsequent Kalashnikov assault rifles. It was a gas-operated weapon, with a long-stroke piston gas system, located above the barrel. Gas piston rod was permanently attached to the massive bolt carrier, with a two-lug rotating bolt that engaged slightly angled cuts in the forward trunnion, pinned to the receiver. The barrel was screwed into the same trunnion and pinned in place. The receiver was formed (stamped) from sheet steel, with bolt guide rails welded inside. The top cover was also stamped from steel and was held in place by a rearward-facing projection on the base of the return spring guide. The return spring guide was a captive telescopic set-up. The charging handle was permanently attached to the right side of the bolt carrier and was of a simple tubular shape. The safety/fire selector lever had a machined projection for the operating finger about the middle of its length. When “on safe”, this lever covered the rear part of the slot for the charging handle but permitted partial retraction of the bolt group. That way, it was still possible to check if the gun had a round in the chamber with the safety on, but the available movement of the bolt group was not sufficient to fully extract it or chamber the next round from the magazine. The barrel of the gun was equipped with a short muzzle brake – compensator, which formed a part of the front sight base. Gun was fitted with a wooden handguard and forend, wooden pistol grip, and wooden or metallic shoulder stock. In the latter case, the stock was made to fold down and forward. The front sight was mounted on the relatively high base near the muzzle end of the barrel; the rear sight, which featured a U-shaped notch, was adjustable between 100 and 800 meters in 100-meter increments. Ammunition was fed from detachable box magazines, made from stamped steel. There was no provision for a bayonet.

 

Kalashnikov AK, pattern of 1949, with stamped steel receiver (AK type 1)
Kalashnikov AK, pattern of 1949, with stamped steel receiver (AK type 1)

 

Kalashnikov AK, pattern of 1949, with stamped steel receiver (AK type 1)
Kalashnikov AK, pattern of 1949, with stamped steel receiver (AK type 1)

 

The “AK Type 2” (produced 1951 – 1955) introduced several important changes to the basic design. First and most important was the new receiver, machined from a single block of steel, which dispensed with separate forward and rearward trunnions of the previous design. Other changes include a new, single-piece pistol grip made from wood, which was attached to a separate base below the receiver using a single vertical bolt. This single-piece grip was less prone to cracks than two relatively thin separate grip panels, used before. Wooden shoulder stock now also has its separate mounting socket, made from steel and pinned to the rear end of the receiver. Less visible changes involved improved springs, made from three-strand wire, stronger top cover, changes in gas piston tube, barrel, and bolt carrier.

 

 

Kalashnikov AK, pattern of 1951, with machined receiver (AK type 2)
Kalashnikov AK, pattern of 1951, with machined receiver (AK type 2)

 

Kalashnikov AK, pattern of 1951, with machined receiver (AK type 2)
Kalashnikov AK, pattern of 1951, with machined receiver (AK type 2)

 

Kalashnikov AK, pattern of 1951, with machined receiver (AK type 2)
Kalashnikov AK, pattern of 1951, with machined receiver (AK type 2), with folding stock and bayonet

 

The “AK type 3” (produced 1955 – 1959) had its barrel, stock, receiver, and its top cover, and some trigger parts made lighter. Several important parts, including trigger and bolt group, were now made from less expensive steel alloy, compared to previous types. A new, aluminum alloy magazine was introduced to further decrease soldiers’ load, although these new magazines were initially restricted to Airborne troops. However, aluminum alloy magazines were not sufficiently strong and durable, and most of the Type 3 AK rifles were issued with new stamped steel magazines, made from thinner steel and reinforced with stamped ribs. The forward sling attachment loop was moved from the forward end of the lower handguard to the gas block, and a new knife-bayonet was adopted along with the gun. The gas system was slightly revised to provide more reliable functioning under harsh conditions.

 

Lightened Kalashnikov AK, pattern of 1955, with machined receiver (AK type 3)
Lightened Kalashnikov AK, pattern of 1955, with machined receiver (AK type 3)

 

Lightened Kalashnikov AK, pattern of 1955, with machined receiver (AK type 3)
Lightened Kalashnikov AK, pattern of 1955, with machined receiver (AK type 3)

 

 

 

Specifications for Kalashnikov AK, pattern of 1949.

AK with fixed stock AK with folding stock
Cartridge 7,62×39
Overall length, mm 870 870 (645 with stock folded)
Barrel length, mm 415 415
Weight with empty magazine, kg 4,3 4,3
Magazine capacity 30 rounds
Rate of fire 600 rounds/minute