Many years ago(2007?), US military was seeking a better rifle. FN's SCAR eventually won, but Knights Armament also submitted their gun called SLICK(S.O.F. Light Individual Carbine Kalashnikov).
It had recirpocating charging handle, Kalashnikov style bolt, monolithic upper, could use Stoner 63 magazine, and have gas piston system and other improvments.
From: Knights Armament
