Abstract: A flame spray device of the internal burner type has a fuel and oxidizer mixture combusted within a combustion chamber feeding products of combustion to a discharge nozzle passage of reduced inner diameter. An axially aligned metal piece injector has a centrally disposed injection bore hole positioned upstream of the combustion chamber and is provided with particles which are fed through the centrally disposed injection bore hole with the injection bore hole opening near the entrance of the nozzle passage. The metal piece terminates in a cone-shaped section with a reduced diameter end proximate to the entrance to the nozzle passage. A knife-edge terminal face is thereby produced intersecting the injector bore hole to minimize turbulence and rotation of the stream of carrier gas containing the powder exiting the injector metal piece injection hole.