The article proposes a thermodynamic approach that allows us to more accurately represent the flow modes of quasi-stationary gas through a long step gas pipeline . It takes into account the peculiarities of the operation of side gas venting devices of small-caliber automatic guns on the principle of automatic operation. We use a combination of the main characteristics that represent the operation of such systems under difficult loading conditions and high temperatures. These are mainly gas consumption, heat transfer losses, gas flow rate, improvement of the approach to the solution of ensuring the appropriate parameters to ensure the reliable operation of the relevant technical systems with the possibility of recommendations after appropriate tests of such products.

Keywords: step gas pipeline, side gas outlet device, gas flow, thermodynamic parameters, heat loss, filling period, gas consumption, automatic weapons systems