This report studied the influence of the cavity in soap from small arms projectiles using down loaded ammunition. To evaluate the effect of barrel twist and down loaded ammunition two barrels with different twist was used and tested at nominally 10 and 20 meters. The ammunition was downloaded to have an impact velocity equal to that at 100 m real range. Tumbling depth and cavity diameter was measured and the results were compared to data from test at 100 m real range. The cavity varied between barrels. Higher twist resulted in a larger tumbling depth and it was concluded that the spin velocity influences the projectile stability and thereby the tumbling depth in soft targets.