UKM-2000
General Purpose Machine Gun UKM-2000 (Uniwersalny Karabin Maszynowy 2000) is a Polish general purpose machine gun designed by a team under leadership of Jozef Gacek who is a director of Technology Department of the Institute of Military and Aviation Technology at Military Technical Academy. (Instytut Techniki Uzbrojenia Wydzialu Uzbrojenia i Lotnictwa Wojskowej Akademii Technicznej). Designers team consisted of workers representing Research Center for Construction and Performance of Military and Aviation Technology at Military Technical Academy (gun, ammunition, and ammunition belt), Metalworks "H. Cegielski-Poznan" S.A. (gun), Metalworks "Mesko" S.A. (ammunition), and Steelmill "Presta" S.A. (ammunition belt). The gun is based on Polish prototype of PKM-NATO machine gun, but its belt-fed system is based on MG42 design. PKM-NATO was a Polish modification of Soviet PKM general purpose machine gun chambered for 7.62x51mm NATO cartridge. The gun has a two-stage feed system using original Polish belt. UKM-2000 was accepted for service in Polish Armed Forces in the early 2000th, replacing Soviet PK and PKM machine guns.
General Purpose Machine Gun UKM-2000D 
UKM-2000P and UKM-2000D
UKM-2000 is a gas operated weapon with four position gas regulator and long stroke gas piston located under the barrel. The weapon has PK style rotating bolt and stamped steel receiver. The gun fires from open bolt. Manual safety lever is located on the left side of receiver above the pistol grip. Gun operates only in full auto mode. Cocking handle is located on the right side of receiver, alongside with ejection port and belt ejection window being located in front of pistol grip. Ejection port is protected by spring loaded dust cover which automatically opens and closes during reloading cycle. UKM-2000 is chambered for 7.62x51mm NATO cartridge, but unlike a Soviet PK, it uses a single stage belt-fed system feeding from the right side. The feed cover can be lifted for the purpose of loading and unloading the weapon. Gun can also be fed using American M13 or Polish GSM-01 desintegrating belts. German SM13 belt cannot be used, because it, and most of the other West European machine guns belts, feed from the left side. UKM-2000 belts are packed in 100 or 200-round steel ammo boxes. (Same as PK ammo boxes). 100-round ammo box can be clamped under the gun's receiver. The quick-detacheable, air cooled barrel is chrome plated and has 4 grooves with 328mm right hand twist rate. The muzzle is terminated with flash supressor. The barrel is equipped with a grip which simplifies and aids barrel change. Folding bipod is attached to the gas tube. The gun can also be mounted on 6T2 or 6T5 tripods from Soviet PKS (PK with tripod) machine gun. The pistol grip is made from brown plastic. The gun in UKM-2000P (P=Piechotny/ for Infantry) version has a fixed skeleton stock made from wood, whereas UKM-2000D (D=Desantowy/ for Landing Troops) version is equipped with right folding wooden skeleton stock. Both versions of stock have compartments for storing accesory cleaning kit. The rail for Night Vision mounting is located on the left side of the receiver. The last UKM-2000P are factory equipped with Picatinny rail above receiver cover. The gun is equipped with open sights graduated from 100 to 1500 meters at 100-meter intervals. Front sight is adjustable for vindage and elevation. Rear sight is mounted on receiver cover. Polish Army uses only 10 UKM-2000D and hundrets of UKM-2000P with Picatinny rail.
UKM-2000D
UKM-2000C
UKM-2000C
UKM-2000C (C=Czołgowy/ for a Tank) is a Polish coaxial machine gun based on standard UKM-2000 design. The weapon is equivalent to Soviet PKTM coaxial machine gun. The barrel in UKM-2000C is not of quick-detacheable type, and is longer and heavier than in UKM-2000 version. The weapon is chambered for 7.62x51mm NATO cartridge, and uses a single stage belt-fed system feeding from the right. Gun accepts M13, GSM-01 belts, but cannot work with SM13 belt. UKM-2000C has modified gas regulator and is equipped with electrical trigger mechanism. There are no provisions to mount bipod, pistol grip, stock, or iron sights, because UKM-2000C is typically permanently mounted on Polish Rosomak armored personnel carriers. (Version of Patria AMV). On UKM-2000C based prototype of UKM-2000CL (CL=Czołgowy Lewostronny/ for a Tank, from left) which uses single stage belt-fed system from the left.
UKM-2000 summary
UKM-2000 is a reliable and light weapon as compared to other general purpose machine guns chambered for 7.62x51mm NATO cartridge. When compared to Soviet PKM it's much simpler to built, and it has the advantage of quick barrel change. On the other hand it is heavier and has increased overall length while having shorter barrel, when compared to its Soviet predecessor. Today Polish Army use a small number of UKM-2000P, UKM-2000D, and UKM-2000C guns, but many PKM general purpose machine guns and PKTM coaxial machine guns still remain in service.
version
UKM-2000P
UKM-2000D
UKM-2000C
cartridge
7.62x51mm
7.62x51mm
7.62x51mm
muzzle velocity
840m/s
840m/s
850m/s
barrel lenght
547mm
547mm
646mm
lenght
1203mm
1203mm
1203mm
barrel weight
2.25kg
2.25kg
3.3kg
weight
8.4kg without ammunition
8.9kg without ammunition
10.7kg without ammunition
feed
desintegrating belt
desintegrating belt
desintegrating belt
rate of fire
750 rpm
750 rpm
750 rpm
UKM-2000D
UKM-2000D sight
UKM-2000D on HMMWV
UKM-2000D