Circular self-propelled sprinkler systems are highly efficient equipment for watering crops by sprinkling. Considering the diameter of irrigation, uniformity and productivity of the installation largely depend on the parameters and relative location of sprinklers on the main pipeline of the sprinkler machine, the assessment of the parameters of artificial rain for compliance with the set values for irrigation conditions requires appropriate theoretical and practical studies. (Research purpose) The research purpose is to theoretically calculate and experimentally confirm the results obtained characterizing the speed and performance of the aerosol jet at the outlet of the sprinkler in the fine sprinkling system, in relation to the main pipeline of the self-propelled sprinkler. (Materials and methods) The ballistic theory of the motion of droplets in the air in the Frene-Serre coordinate system perpendicular to the irrigation plane was used to construct a mathematical model of the motion of an aerosol jet. A set of sprinklers located on the main pipeline of a wide-scope circular sprinkler machine of the T-L Irrigation company was considered as an object of research. (Results and discussion) A mathematical model has been proposed for calculating the movement of an aerosol sprinkler jet in the air, which makes it possible to bring the volume flow rate of the sprinkler to an equivalent diameter and wetting depth in the irrigation plane. It has been shown that the data obtained make it possible to predict for a given set of sprinklers the depth of irrigation per unit of irrigated surface in the plane of the figure formed by two circles determined by the circular motion of two adjacent support trolleys of the machine. (Conclusions) It was determined that in order to bring the uniformity coefficient of circular sprinklers to a normalized value, when compiling appropriate mathematical models of the irrigation process, further adaptation of the movement of a single drop in the air to the parameters of artificial rain formed by the spray jet of the sprinkler is required.