Not quite "all". I have examined at least one V-series P99 prototype that was rifled with Metford-style (H&K didn't invent it) rifling. It was rifled, all right, but the shadows were the only thing that gave it away. I saw another that had its bore drilled off-center in the barrel (I don't recall if it was at 6 or 12 o'clock) presumably to compensate for a machining error on the slide.All Walther P99 barrels are conventional land and groove rifled. Not polygonal like Glock/HK.