We Need to Talk About the PK Machine Gun
Kalashnikov’s Machine Gun Almost Matches the AK Rifle in Global Reach and Emulation
The PK family of general purpose machine guns have been an enduring presence in armed violence around the world and have been copied in diverse forms. Beginning its career in the Soviet Army in 1961, PKs are almost as omnipresent as their AK rifle cousins in ongoing Middle Eastern, African and South Asian warzones — either in the hands of Syrian, Iraqi and Afghan government soldiers, Taliban, ISIL and Kurdish militia or mounted within Soviet era armoured vehicles and the backs of pickup trucks serving all of the above factions. Although PKs and their knock offs have been wielded by diverse combatants ranging from 1980s Soviet conscripts humping the mountains of Afghanistan to rebels in Libya’s desert wastes overthrowing Colonel Gadaffi in 2011, they have not received the same level of pop culture familiarity in Joe Public’s mind as the M60 machine gun which got its spotlight in the Vietnam War.
Origins: A Quest to Replace Many Guns with One
At the end of World War 2, the Soviet Army counted a multitude of machine guns in its armouries. Infantry squads possessed the DPM Degtyarev light machine gun with its distinctive gramophone record shaped magazine and its belt fed successor, the RP-46. The medium Goryunov SG-43/SGM and heavy Maxim M1910/30 machine guns, mounted on wheeled carts to facilitate movement, were distributed at company and battalion level. The Soviets had noted that the defeated Nazi German invaders had the MG34 and MG42, universal weapons that filled both the light ‘assault’ and heavy sustained fire roles. Just as the US military sought to replace the Browning Automatic Rifle and various models of the M1919 Browning medium machine gun with a single platform, the Soviets were arriving at the same idea.
While the DPM would be replaced by the RPD (Ruchnoi Pulemyot Degtyarev), a handy light automatic weapon chambered for the intermediate 7.62x39mm round, the Soviet Army still desired a machine gun for the full powered rimmed 7.62x54 round which was more mobile than the Goryunov and Maxim. One of the aspiring designs by Grigory Nikitin and Yuri Sokolov — the PN (Pulemyot Nikitin) — held much promise but its self regulating gas regulator malfunctioned when wet, forcing the weapon to fire single shots until it could be dried. The team of Mikhail Kalashnikov, then engaged on reworking the AK rifle into its AKM successor, submitted their own machine gun which won the tender because it was available sooner. Part of its appeal lay in its manually controlled gas regulator which was more reliable than the Nikitin — Sokolov contestant; the Kalashnikov design would also save money because it was compatible with the non-disintegrating cartridge belts of the outgoing Maxims and Goryunovs, which populated quartermaster warehouses in the thousands.
Description and Variations
The PK (Pulemyot Kalashnikov — ‘Kalashnikov machine gun’) is chambered for the M1908 7.62x54 mm round — a full power cartridge first used in the pre World War I Mosin Nagant M1891 rifle and equivalent to the 7.62x51mm NATO round. What distinguished the PK from its rivals was its light weight — 9 kg (19.8 lb) as opposed to the M60 (10.4 kg/22.93 lb) and MAG (11 kg/24.25 lb). The succeeding PKM, to be discussed later, shed even more weight for 7.5 kg/16.54 lb — comparable to the FN Minimi chambered for 5.56x45mm. Factors responsible for its lighter weight were the skeleton shoulder stock instead of a solid one, the absence of a barrel heat shield or foregrip and a shorter receiver block than its competitors.
Unlike most modern machine guns, the PK’s non disintegrating belts are fed from the right side while spent cases are ejected from the left. While more convenient for reusing than disintegrating link belts on rival designs, the PK’s belts constitute a tripping hazard and collect dirt if left to drag on the ground. If shooting from a standing position, a right handed user would risk having hot casings strike his support arm. PK gunners from non-state groups tend to grip the weapon by either its bipod legs or the quick change barrel’s carry handle to avoid the expelled casings and to deal with the absence of a foregrip.
When fired from the prone position with bipod deployed, the PK is accurate up to 1500m, assuming the gunner is bracing its stock securely against his shoulder. Its rate of fire at 650 rounds per minute makes it relatively easier to save ammunition compared to faster firing weapons like the MG3. On the other hand, when the PK is elevated off the ground by a tripod for the sustained fire role, accuracy is severely degraded by the recoil lifting its feet upwards unless immobilized by sandbags and other heavy impediments. The manually operated gas regulator for cycling the weapon has three positions — if jammed with dirt or mud, the additional settings force additional gas to cycle the weapon at higher rates of fire. Leaving the regulator on these emergency settings when the weapon is clean will consequently wear out the action prematurely.
As befits its General Purpose Machine Gun (GPMG) specification, the PK was produced in various forms. The original PK was named PKS (S — stankoviy, ‘heavy’) when fitted to a Samozhenkov tripod for garrisoning fixed positions in the sustained fire role.
Approved as a coaxial weapon in 1962, the PKT (T for tankoviy) coaxial machine gun eschewed the pistol grip, bipod and stock for a firing solenoid; its barrel was extended to avoid changing the main gun sights which were calibrated for the SGMT it was replacing in the T-54 medium tank. While usually remotely fired from the vehicle gunner’s handgrips, an emergency trigger on its rear can be used for direct manual shooting should electrical power be cut off.
When fitted with spade grips and a butterfly trigger, the PKB (B for bronetransportere) was intended to replace the SGMB pintle mounted machine guns on early generation armoured personnel carriers like the BTR-50P and BTR-60PA. The PKB may be the least commonly seen version because these vehicles were all replaced by more heavily armed APCs with enclosed turrets utilizing the PKT as a coaxial companion to the KPVT 14.5mm heavy machine gun.
Most Soviet and Russian small arms undergo a major product improvement change resulting in an ‘M’ suffix and the PK was no exception. Debuting in 1969, the PKM (M — modernizirovanniy, ‘modernized’), whose weight reduction benefits were mentioned earlier in the text, featured a smooth barrel without fluting grooves, a shortened flash hider and a hinged shoulder flap on the stock. The heavy 7.7 kg/17 lb Samozhenkov tripod for the PKS was displaced by a less burdensome 4.5 kg/10 lb design by Leonid Stepanov; the corresponding designation was PKMS along with the PKMT and PKMB for vehicles.
Ammunition for the PK/PKM is supplied in 100, 200 and 250 round belts. In the light ‘assault’ role, the weapon would be fitted with a 100 round ammunition box that clips to a bracket in front of the trigger group. PKSs and PKMSs are usually fed from the 250 round box which attaches to the tripod’s right leg. Both 100 and 250 round boxes mount canvas carry handles for portability. For maintenance, the lower horizontal rung of the PK/PKM’s skeleton shoulder stock holds cleaning gear while a swabbing rod can be disassembled to clip to the weapon’s right bipod leg.
While BMP-1 and BMP-2 infantry fighting vehicles feed their coaxial PKT/PKMTs from an integral 2000 round box, Russian tanks still feed their coaxials with the same 250 round boxes as their infantry counterparts. In contrast to the infantry PK and PKM’s barrel which needs changing after 200 rounds of sustained fire or 400 rounds in bursts, the heavier barrels of the PKT/PKMT are rated to last for 500 rounds if burst fire discipline is adhered to.
Going to War Globally
According to the 1991 US Army publication FM 100–2–3 The Soviet Army: Troops, Organization and Equipment, PKMs were issued to Motor Rifle infantry as a company level weapon. MR companies embarked on wheeled BTR series armoured personnel carriers (APCs) rostered three PKM gunners serving alongside the anti-tank guided missile operators of the weapons platoon. Since the BMP series of tracked infantry fighting vehicles (IFVs) mounted their own anti-vehicle cannons and ATGMs, their assigned troops eschewed emplaced missiles, receiving six PKMs instead. The weapons platoon’s role was to provide supporting fires which surpassed the lethality and range of the MR company’s three rifle platoons who fielded lighter weapons like the AK-74 assault rifle and RPK-74 light machine gun.
Soviet airborne infantry companies officially held no organic PKMs because they lacked a weapons platoon like MR companies. Instead, they relied on their BMD air transportable troop carriers for direct fire support. During the Soviet war in Afghanistan however, the prevalence of mines and the rocky mountain topography turned the thin skinned BMD-1 into a death trap with its mobility heavily curtailed. Compelled to operate in dispersed groups on foot while battling a hit and run adversary, the paratroopers unofficially received PKMs that allowed them to engage mujahideen fighters beyond the range of their usual 5.45mm small arms while providing a heavier volume of fire than their squad marksman’s SVD scoped rifles.
Just like Kalashnikov’s AK progeny, the PK and PKM have been used by national armies and dozens of non-state guerrilla movements. A full listing of where this weapon has mowed down its enemies would be too long to document but examples of it playing for both or more sides in the same war stand out the most. Soviet soldiers trained with this weapon for a possible war with NATO in Europe and humped them around the mountains and grasslands of Afghanistan; the mujahideen fighters opposing them in the latter theatre gladly used whatever examples they could lay their hands on. Years later in the same land, American and other ISAF soldiers would simultaneously mentor Afghan National Army soldiers armed with the PKM or scramble for cover when Taliban fighters opened up with the same weapons in locations ranging from Combat Outpost Keating to Helmand’s Green Zone. Russian troops, their local allies and separatist guerrillas all exchanged rounds with PKMs in the Chechen Wars from December 1994 till their conclusion in 2009. ISIL minions invading Iraq from eastern Syria to form their caliphate would have used the PKM for conquest and filling mass graves with bullet perforated captives, while Iraqi soldiers and Kurdish militias rallied against the hordes in Mosul and Raqqa under its wall of fire.
Dozens of former Soviet client states have built PKs with or without license and added their own local quirks. Hailing from the former Yugoslavia, the Zastava M84 has a solid stock, combining the PKM’s smooth barrel with the original PK’s long flash hider. Bulgaria’s Arsenal AD offers the MG and MG-M1 in the same 7.62x54mm as the original, while the MG-M2 is chambered in 7.62x51 mm NATO with left side feeding. One of the most bizarre knock offs which has appeared in Syria is the North Korean Type 73, featuring a grenade discharger muzzle adaptor and dual feed system for belt and top loading box magazines.
American private military contractors working in Iraq who came to appreciate the PKM have provided a market for US companies offering replacement parts and customization options not normally seen on Russian military models: the most notable covered in the January 2008 issue of Soldier of Fortune magazine included replacement barrels and improved receivers from VLTOR and Blackheart International’s PKM SOPMOD rail mounted foregrip which solves the PKM’s lack of a decent forearm for hip firing.
The Future of Kalashnikov’s Machine Guns
Even though the PKM was originally a company level weapon in Soviet and Russian practice, the need to give more operational autonomy and weapons engagement range capability at lower sub unit echelons has led to it displacing the RPK-74 in many infantry squads. This move mirrors the British Army’s purge of the magazine fed L86A-2 Light Support Weapon from their infantry sections in favour of the belt fed L110A-2 Para Minimi, L7A-2 GPMG and L129A-1 Sharpshooter rifle.
As part of its modernization and organizational reform, the Russian military has begun replacing the PKM with the PKP Pecheneg. Rather than a quick change barrel, the new weapon alleviates accumulated heat with cooling ribs built around a heavy fixed barrel which draws air at the rear of its insulating sleeve and forces it towards the muzzle. The PKP shares the PKM’s deficiency of not possessing a proper forearm and its bipod is mounted too far forward to be held by hand while firing from the hip.
While the PKM may lose its infantry job to the PKP, the armoured vehicle co-axial PKMT has a bright future with no planned replacement. Its portfolio has expanded, since it is a weapon option for the T05BV-1 remote weapon station of the T-90MS main battle tank. When Russia rolled out the Uran-9 unmanned ground combat vehicle (UGCV) in the Syrian civil war, the 12 ton robot critter’s options for crushing anti-Assad rebels counted a PKMT to round off its 30mm cannon, thermobaric rockets and Ataka anti-tank missiles. There is little doubt that future Russian robot vehicles will create more opportunities for Kalashnikov’s enduring GPMG.
