AK108 - Design Details

Design Details

The AK-107 and AK-108 represent a significant change to the Kalashnikov operating system originally designed in the late 1940s. The new rifle features a balanced system that functions along the lines of Newton's third law of motion, which states that for every action there is an equal and opposite reaction. This system uses a recoil-reducing countermass mechanism with two operating rods that move in opposite directions, thereby providing "balance". One operating rod, the upper, has a gas piston facing forward while the lower also has a gas piston. The gas tube at the forward end of the handguard is double-ended to accommodate the two rods. The enlarged gas tube cover of the upper handguard guides both rods in their travel.

When the rifle is fired, gas is tapped from the gas port to enter the gas tube, driving the bolt carrier to the rear and the counter-recoil upper rail forward. The critical timing of the reciprocating parts is accomplished by a star-shaped sprocket that links and synchronizes both components, causing both to reach their maximum extension, or null point where forces are exactly equal, at exactly the same instant. The felt recoil is therefore eliminated, enhancing accuracy and assisting control during fully automatic fire. The travel distance of the AK-107 reciprocating parts is less than other Kalashnikov designs, so the cyclic rate is higher at 850–900 rounds/min rather than 600 rounds/min on other AK rifles. However, as the felt recoil is virtually eliminated, the manufacturer claims that accuracy is enhanced, especially during burst fire. An enhancement of 1.5 to 2 times, compared to the original AK100 series, has been reported.

The AK-107 is a selective fire weapon, with a three-round burst capability in addition to semi-automatic and fully automatic firing modes. The system on the AK-107 resets to three-round burst each time the trigger is released, even if only one or two rounds were fired. External differences between the AK-107 and its predecessors are minor. They include a modified ejection port and a much thicker operating rod cover. The method of attaching the receiver cover now involves a rotating latch in place of the traditional Kalashnikov button at the rear of the receiver cover. The rear sight is also attached directly to the receiver cover rather than to the receiver itself and the selector has four positions instead of three. Optical and night sights can be installed, the rifle can also accept a 40 mm GP-25 grenade launcher.

The AK-108 is a version of the AK-107 chambered in 5.56x45mm NATO. Like the rest of the AK-100 series, these newer AKs use synthetic materials such as black fiberglass-reinforced polymer for the pistol grip and heat shield. This material is more cost efficient and much stronger than the original AKM/AK-74 wood furniture.