I claim the ornamental design for a bull tire swing, as shown and described.
FIG. 1 is a top perspective view of a bull tire swing;
FIG. 2 is a front elevational view thereof,
FIG. 3 is a left side elevational view thereof;
FIG. 4 is a rear elevational view thereof,
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The ornamental design which is claimed is shown in solid lines in the drawings. The broken lines in the drawings are for illustrative purposes only and form no part of the claimed design.