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Based on test results of projecting four different types of spherical fragments, diameters of which were 3.175 mm, 4.763 mm, 5.56 mm, and 6.35 mm, respectively, into the biological soft tissues and the soap blocks used as simulants, an estimation of the physical characteristics of wounds inflicted by spherical fragments was established in this paper. With impact velocities in the range of 4501,500 ms, all four types of spherical fragments showed little variation in drag coefficients for each medium. Some specific wound characteristics such as amount of debrided tissue, volume of the wound channel, etc., can be predicted as functions of energy transfer for spherical fragments of less than 1 gram.

This paper reports the wounding effectiveness tests of four kinds of spherical steel fragments, striking against live tissues at various velocities. The most pronounced wound characteristic for the spherical fragments was that the entrances were larger than the exits the higher the striking velocity, the larger the size of the wound. The skin near the entrance tended to be torn away when the striking velocity was above 1,200 ms. As a general rule, most exits appeared to be circular with a diameter slightly bigger than that of the fragment. Shapes of the wound channels were conic in general. The channel volumes were proportional to the striking velocities of the fragments in the case of two spheres having the same striking energy, the small one would produce larger volume of wound channel and amount of debrided tissues. The energy release rate for smaller fragments was higher than that for larger ones.