An improved kinetic spray nozzle system design is disclosed. The nozzle includes an improved powder injector having an injector tube and a sleeve wherein the injector tube is received in the sleeve and secured to the sleeve. The powder injector further includes an air gap defined between an inner diameter of the sleeve and an outer diameter of the injector tube wherein the air gap is from 50 to 200 microns. The improved injector is capable of spraying a variety of powder materials including hard and “gummy” powders for without clogging for extended periods of time whereas under similar spray conditions previous designs became completely plugged within minutes. The improved injector design enabled the use of higher main gas temperatures to achieve improved coating formation and deposition efficiencies. Most importantly, the improved design makes it possible to use the kinetic spray system with a wide range of powder materials in a manufacturing setting without interruptions caused by powder injector clogging related problems.