OPTIMIZING PROJECTILE DESIGN IN ARTILLERY SYSTEMS: THE ROLE OF BLOW-BY IN GUN PERFORMANCE & TUBE WEAR

This study examines the impacts of blow-by phenomena in 155mm projectiles and the effectiveness of obturators on sealing gun tube pressures. Six tests were conducted at Yuma Proving Ground (YPG) using a 155mm projectile with only minor configuration changes of driving band systems. Four rounds were fired out of a fourth quartile wear gun tube. Two were equipped with obturators and two were not. The last two projectiles were fired with obturators in a first quartile gun tube. These tests were conducted in a howitzer with a 39- caliber barrel at a top zone charge. The research quantifies pressure distribution variations within the gun tube and analyzes asymmetrical blow-by pressure patterns under different firing conditions. Results demonstrate that obturators significantly reduce blow-by pressures, by as much as 93.5%, and gun tubes with less wear on them exhibit lower blow-by. Pressure measurements revealed distinct asymmetrical patterns, critical to understanding the way that the gun tube wears. These findings provide valuable insights for projectile design optimization and performance enhancement in large-caliber artillery systems.