The ornamental design for upper receiver cut-outs, as shown and described.
FIG. 1 is an isometric front view showing the right side of my design for upper receiver cut-outs;
FIG. 2 is a right side view thereof;
FIG. 3 is a left side view thereof;
FIG. 4 is a top view thereof;
FIG. 5 is a bottom view thereof;
FIG. 6 is a front view thereof; and,
FIG. 7 is a back view thereof.
The surface shading is for purposes of illustrating the contour and appearance of the claimed surfaces upon which it is illustrated, but is not actually seen on the surface of the upper receiver. The broken lines are used to show unclaimed portions of the invention and form no part of the claimed design.