The C Series is a mid-level optic, while the B Series is a high performance, elite-level optic.
Across the board, the B Series has a ~5-10% increase in performance compared to the C series. This difference will be most noticeable when spending longer time behind the glass. B Series optics have a larger sweet spot & dash.The B Series’ internal optical system uses a higher grade of glass throughout the entire unit. B Series units are produced individually and undergo a more rigorous inspection, while the C Series is produced in the hundreds, and sample inspected. The C Series has a polymer frame lighter than the magnesium frame of the B Series.
Specific features can be viewed on the individual product pages.