The ornamental design for a mgrscombomapprotractor, as shown and described.
FIG. 1 is a top plan view of a front surface of a MGRS combo map protractor showing my new design; and,
FIG. 2 is a rear plan view of a rear surface thereof.
It is understood that the sides are of no substantial thickness. All the markings, lines, numbers and all remaining indicia shown in the top plan view are claimed. Nothing is claimed with respect to the rear plan view. The outer rectangular broken lines shown in FIGS. 1 and 2 are for illustrative purposes only and form no part of the claimed design.