The LWRCI M6-AK upper is an M6A2 style upper chambered in the 5.45x39mm cartridge. It features a 14.7” barrel with permanently attached A2 flash hider. It has the LWRCI Mark 1 ARM-R rail system and utilizes LWRCI’s patented short-stroke gas-piston operating system.
The 5.45x39mm cartridge was developed as the Soviet’s answer to the American and NATO countries 5.56x45mm cartridge. It was chambered in their AK-74 rifles and its ballistics closely mirror those of our 5.56 round.
There are currently large quantities of this ammo available to American shooters at incredible prices. Most of the surplus ammo is mildly corrosive, so careful cleaning of the rifle is required after every session. One great advantage of shooting this ammo out of a piston gun as compared to a direct impingement gun, is that all of the dirty / corrosive propellant gases are vented at the gas block instead of being blasted back into the receiver where they can foul not only the upper but the lower as well. The cleaner operating characteristics of piston guns make sense with any ammo but when shooting corrosive ammo it becomes a no brainer.
Why the 5.45 upper?
The reason we built these uppers is to take advantage of this cheap supply of ammo. Owners of our rifles typically shoot a lot. If you figure that an average upper has a minimum lifespan of 15,000 rounds and that most of those rounds will be spent training, shooting paper targets and the like. Why would you spend an extra $3600 to accomplish that?
Caliber Cost per round Number of Rounds Cost
5.56 NATO 0.35 15,000 $5250
5.45x39mm 0.11 15,000 $1650
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