Abstract
Evaluation of the diameter of a bullet which caused an entrance hole by measuring the diameter of the color rings developed through use of the bullet hole identification kit (BTK) is presented. A direct estimation of the diameter of the bullet can be made, or a range of diameters can be determined. This range depends on the material of the target, and to an extent, on the kind of support behind the target. In the case of woven cotton textiles, this range was found to be small, and larger in other textile materials. Even in these latter cases, one can discriminate between the large and small diameters (for example, those of the 0.22 and 0.38 calibers). These results can be very useful when targets are dark colored or soiled to a degree where the black ring (“ring of dirt”) around the entrance hole is unrecognizable.
