This paper, by combining a longer barrel (200 mm) with the gas shroud, investigates the correlation between the state of HVOF sprayed particles, that is velocity and molten fraction, with the density and oxygen content of the resultant coatings of 316L stainless steel. Realization of dense and low-oxygen content coatings by optimizing the operation conditions is demonstrated. The inert gas fusion method is used to determine the oxygen content. It is observed that the porosity of the layer decreases with increasing particle velocity. From a particle speed of over 750 m/s, a porosity below the detection limit of the air permeability tester is determined. A combination of gas shielding and optimized pipe length as well as optimized operating conditions made it possible to achieve very dense layers with low oxygen contents of less than 0.2% by weight. Paper includes a German-language abstract.