Abstract: A formula for estimating total mass loss of projectilewas developed with the assumptions of the peeling of molten surface inprojectile nose as the primary cause of mass loss and the frictional heattotally accepted by projectile. In combination of the linear relationshipbetween friction work and work done by pressure, the receding displacementof every point on projectile surface, which is vertical to the projectilesymmetry axis, is obtained based on the formula for estimating total massloss. Thereby, the variation of projectile shape is simulated. The shape ofresidual projectile, the depth of penetration (DOP) and projectile mass lossobtained by calculation are in good consistency with the correspondingexperimental results.