With the exact same swappable barrel system as the 455 and the same reliable polymer magazine system, the 457 is without a doubt the best rimfire platform CZ has ever fielded. The 457 now features a trigger adjustable for weight, creep and over-travel. The stamped bottom metal of the 455 is gone, swapped for a classy two-piece interlocking system. To make scope fitment easier, CZ ditched the 90 degree bolt rotation in favor of a 60 degree, allowing for larger ocular bell diameters with lower ring heights.