For years, Primary Weapons Systems has been building some of the most reliable piston-driven AR rifles on the market, and the latest-generation MK107 is no exception. This pistol is built on a forged upper receiver mated to a slim and smooth free-floating handguard, utilizing the VLTOR KeyMod system. With the 7-inch QPQ-coated, button-rifled, barrel chambered for .223 Wylde and topped off with a Triad flash suppressor, the MK107 is compact, light and accurate. Author David Bahde was impressed, noting, “This weapon really shines at CQB work…compared with an AK pistol, the difference is striking. I could shoot this all day without issue, and I did.” Want to know how the potent MK107 pistol stood up to rifles when it came to accuracy? Then check out the 2014 issue of The Complete Book Of Guns, available on newsstands and digitally on July 9, 2013. To subscribe, go to personaldefenseworld.com/subscribe.