The ornamental design for a bow blind, as shown and described.
FIG. 1 is a perspective view of a bow blind showing my new design;
FIG. 2 is a perspective view of the opposite side thereof;
FIG. 3 is a front elevation view thereof;
FIG. 4 is a rear elevation view thereof;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof; and,
FIG. 7 is a right side view thereof.
The broken line showing of blind sleeves in FIGS. 2 and 3 and of a bow in FIG. 7 is included for the purpose of showing environmental portions of the bow blind and forms no part of the claimed design.