This paper outlines the findings of theoretical investigations into the grain materials grinding process in agriculture, focusing on the particle breakdown occurring at the moving edge of the rotor groove relative to the fixed edge of the stator. The choice of grinding methods is influenced by the processed feed, its intended purpose, the adopted feed preparation technology, and the specific farm animals involved. The study highlights the significant variations in the grinding process due to differences in dimensional characteristics and strength properties of grain materials, which impact the selection of working chamber parameters and operating modes. The paper introduces a hexagonal rotary crusher design and technological scheme, which offers the flexibility to adjust the amplitude-frequency characteristics of the working elements, energy of the process, and grinding quality within a wide range. Further research on the system dynamics requires experimental studies of grain material grinders utilizing diverse destruction methods. This study aims to advance understanding of the grain materials grinding process and optimize feed processing techniques for improved livestock productivity and product quality.