AK-107 / AK-108 animation

Steve Johnson
by Steve Johnson

It has been a while since I have posted an animation. This one, author unknown, shows how the balanced gas operating system works in the AK-107 and AK-108 rifles.

Source: i40.tinypic.com

( If the animation is not playing, try this link: click here)

Wikipedia explains how the system works:

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-dampening 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 bolt carrier 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 has been reported.

The system was previously used on the prototype AL-7 and AEK-971 rifles in the 1970s.

Hat Tip: fuliginosus @ guns.reddit.com

Steve Johnson
Steve Johnson

I founded TFB in 2007 and over 10 years worked tirelessly, with the help of my team, to build it up into the largest gun blog online. I retired as Editor in Chief in 2017. During my decade at TFB I was fortunate to work with the most amazing talented writers and genuinely good people!

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  • Sven Sven on Oct 20, 2012

    Reakce zpětného rázu zůstává celá zachována, pouze je pomocí ozubeného pastorku, který je součástí pouzdra zbraně, rozložena do mnohem delšího časového úseku, než u klasických zbraní.

    Sorry my english:
    Reaction of recoil stay full, only by help of teeth wheel, which is solid component of cascet weapon is this force unfold to very longer time interval, against classic weapons.

  • Sven Sven on Oct 20, 2012

    Lépe řečeno :
    Zpětný ráz je stejný jako u klasického AK (do okamžiku odemčení), kdy projektil přeběhne piston. Dále platí předešlý příspěvek.

    Better say :
    Recoil is the same how has classic AK ( to time unlock ), when projectile run acros the piston. After is valid previous report.