City Destroyer: Meet the Russian Army's Super Gun These guns have devastated fortifications from Afghanistan to Ukraine. Here's What You Need to Know: The M240 mortar can fire a variety of special-purpose rounds. Self-propelled heavy mortar carriers are ubiquitous in modern mechanized armies. Mounted on light armored carriers and placed at the disposal of battalion commanders, such vehicles can deliver heavy and fast-responding indirect bombardments with 120-millimeter shells. When compared to self-propelled howitzers of similar caliber, mortars are lighter and require a smaller logistical train, but have significantly shorter range. The United States Army mounts 120-millimeter mortars on wheeled Strykers (the M1129) and M113 tracked vehicles (designated the M1064). Russia fields its own 120-millimeter self-propelled vehicles, the 2S9 NONA.