1.) Stand in front of a HEMTT.
2.) Pick the portside windshield and shoot it until it breaks.

3.) Note how the starboard windshield also breaks as well, even though it hasn't been shot at all (and vice-versa).

1.) Stand in front of a four-pane house window.
2.) Shoot one of the corner glass panes until it breaks.
3.) Note how the other three break as well, when they're separate pieces.