A 2D and 3D Topography Measurement and Correlation System was developed at NIST for certification of NIST Standard Reference Material (SRM) 2460/2461 Bullets and Cartridge Cases. Based on this system, a prototype system for signature measurement and correlation of fired bullets has been recently developed at NIST for bullet identifications. The 3D topography data of the land engraved areas (LEAs) of fired bullets are captured by a commercial confocal microscope. The LEAs were processed by the “edge detection” method to determine the “striation density.” Then surface areas with low striation density on the LEA could be masked out from correlation. The modified 3D micro-topography data on the remaining “valid correlation areas” are compressed into a 2D profile which represents the 2D ballistics signature of the LEA. A correlation program using two methods has been developed for matching the paired profile signatures: the “CMS” (Consecutive Matching Striae) method used by many firearm examiners and the CCFmax (cross correlation function maximum) method developed by NIST, based on analysis methods in surface metrology. The CMS criteria were applied to topography images here and not to traditional reflectance microscopy images. In 2010, a set of 20 known-matching bullets fired from ten consecutively manufactured barrels (two bullets from each barrel) were tested. Their 3D topography images were captured by the confocal microscope at NIST, and correlated by the prototype ballistics identification system using the cross-correlation function maximum (CCFmax) as a correlation indicator. The correlation result was excellent: correlation values of all ten pairs of known-matching bullets scored highest on all correlation lists, yielding a correct identification rate of 100%. For the 60 pairs of matched LEAs (each bullet includes six LEAs), correlation values of matching LEAs scored highest on 59 out of 60 correlation lists, yielding a correct identification rate for individual LEAs of 98.3 %. In 2010, an additional set of 15 unknown matching bullets fired from the same set of 10 barrels was blind tested. These bullets were correlated with the 20 known-matching bullets mentioned above, making the total number of correct matching pairs equal to 30 (15  2). Both the CCF and CMS method were used and showed excellent correlation results. When using the CMS method, one matching pair did not meet the selected CMS criterion (3X) for a “match”, but 29 out of 30 pairs of matching bullets were correctly identified, yielding a correct identification rate of 96.7%. When using the CCF method, all 30 pairs of matching bullets scored at the topmost position on their respective correlation lists, yielding a correct identification rate of 100 %. The comparable performances of both mathematical models point to the potential unification of decades of CMS empirical data and new surface metrology systems.