Abstract: Describes a novel technique developed to measure the deformation process of hollow projectiles penetrating concrete targets, applying strain gages attached to the inner walls of the projectile, together with projectile borne testing and storage device. Experiments were carried out to measure, record, and playback the deformation process of 35CrMnSi projectiles against concrete targets at low velocities (150～300 m/s). Profiles of strain time relationship were successively obtained. Relationship between strain development and projectile deformation process is discussed. Experimental results show that the projectile material goes through compression and tension deformations intermittently.