The length of the line (e.g. The tail) is a surface projection of the drill hole on the surface of the map. Since the holes were drilled close to vertical ( -85 deg collar angle ) the hole projects on the surface as being short. M04 was 448 meters long. Contrast that with the projection of the 507 meter hole 44 with its long 'tail' which was drilled at a collar angle of -50 deg. ... Been There