Jad
Sure, they can.
For example, I like rules, written to me by
Buckaroo:
Quote:Z-fire range limited to 20 hexes or less (<1,001 m). Z-fire allowed only by units whose slot 1 weapon is a machine gun (MG) or cannon (e.g., tank, mortar, rocket) or shape charge (e.g., pzschreck, bazooka). For example, rifle squads may not z-fire, even though they have a LMG in slot 2. Z-firing units may simultaneously fire slot 2-4 weapons regardless of their type. Arty may z-fire further than 1,000 m ONLY if the firing unit has LOS on the target hex at the moment of firing.
Resonable and easy limits! Easy to use, easy to remember. Z-fire by MG and Cannon units is quite enough. Usually most Z-fire do infantry units, but if we exclude it - it still enough tactical suppression from other units.