The ornamental design for a positively engaginghelmetbracket with set back, as shown and described.
FIG. 1 is front perspective view of a positively engaging helmet bracket with set back showing our new design;
FIG. 2 is front elevational view thereof;
FIG. 3 is a right side elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a top plan view thereof;
FIG. 6 is a bottom plan view thereof; and,
FIG. 7 is a front perspective view thereof, showing the article in its environmental use.
The broken lines representing the helmet and disclaimed portions of the design are for illustrative purpose only and form no part of the claimed design.