On the face of it, it looks like SIG SAUER shrunk an AR-15 down to 9mm cartridge length and voila! The new MPX. The gunmaker touts the result as revolutionary. As RF will tell you, this kinda stuff gets filed under “evolutionary” in my book. LEO only? Nope. As Dracon 1201 points out below, the video above shows an MPX C carbine in semi auto only with a 6.5″ barrel and 9.5″ permanently attached muzzle break—making it a semi only 16″ barrel carbine. While SIG’s $1207 msrp P556 pistol isn’t exactly a sales phenom, an MPX might fly off the shelves. Like everything else these days. At any price. Maybe I’ll run into the full-auto MPX at the NDIA . . .