The soft deformable metallic rotating band of large caliber projectiles prevents the gas leakage between the gun tube wall and the shell body by the band pressure on contact surfaces during the launch cycle of the gun. High rotating band pressures can lead to problems concerning gun tube wear, fatigue, and strength. The effects of changes in construction of rotating band and long range artillery projectile shell body on gun tube loading are studied experimentally. A practical analysis method for tube inner wall pressure computation from outer wall strain measurements is presented. The method is based on assuming stepped pressure load affecting on tube inner wall surface, when the projectile passes the measurement point. Although the analysis method was simplified, it was found to give useful and reliable results for comparative verification of different shell and band structures and their influences on gun tube loading. The structural design of the shell body and the rotating band were shown to be the most important aspects to cause the extreme loadings on the gun tube.