:
October 8, 2022: The U.S. Army has been using Israeli and British technology to improve its mortars. The M224A1 60mm mortar has been steadily improved since 1978. It weighs 17kg (37.5 pounds) and has a max range of 3,800 meters. The current (A1) version entered service in 2011 and is 20 percent lighter, easier to use and more accurate. The most used shell is high-explosive. Each one weighs 1.66kg (3.65 pounds). Each infantry company has two 60mm mortars, providing the company commander with his own artillery support that is always available. Normal crew of the 60mm mortar is three men but one man can just carry the tube and fire shells less accurately and at shorter distances.
The U.S. M252A1 81mm mortar was adapted from the British L16A2 mortar that entered service in 1987. The updated A1 version entered service in 2016. This system weighs 36 kg (79 pounds). The Americans have made some improvement in the sights and shells. Current max range is 3,400 meters. Each Infantry battalion has a mortar platoon with 8 or 9 81mm mortars. Each has a four or five-man crew, which enables the mortar to be disassembled into components light enough to be carried by the crew. The most commonly used shell is the 4.5kg (10 pound) high-explosive one with a max range of 5,900 meters. The shell can kill or wound anyone within 35 meters (115 feet) of the detonation. This shell is about as effective as the 75mm artillery shell, which was a common artillery shell during World War II (1939-45) when 81mm mortars were first used.
The M121 (vehicle mounted)/M120A1 (towed) 120mm mortars were introduced in 1990 and based on the Israeli Elbit Soltam K6 lightweight (146 kg/320 pounds) mortar system. Elbit has established a manufacturing operation in the United States and is one of the manufacturers of the American 120mm mortars. Meanwhile the K6 has been exported to over a dozen countries. The 13.7 kg (20.2 pound) high explosive shell has a max range of 7,800 meters. The shell has the explosive equivalent of a 105mm artillery shell.
The 81mm and 120mm mortars are often fired from a wheeled or light armored vehicle. The 120mm mortar is not designed to be man-packed, but transported in or towed by a vehicle.
Since the late 1990s there have been efforts to develop usable (reliable and affordable) 120nn GPS guided mortar shells. More recently these efforts have included 81mm mortar shells. The U.S. military continued work on these guided shells, occasionally using them. This was usually to test a new version.
The American 17.3 kg (38 pound) 120mm XM395 round entered service in 2011 has been in development since the late 1990s. It has a range of 7.5 kilometers, and using GPS guidance would land within a 10 meters (30 feet) circle. What made the XM395 more affordable was that its guidance system was in a fuze replacing the standard one. The ATK fuze required an additional item of equipment. This was a small device that enabled you to enter the GPS coordinates into each ATK fuze so it knew where to go. The cost per fuze had steadily gone down from $10,000 each to about $5,000. The XM395 is not regularly used because the unguided shells are accurate enough for most battlefield situations.
Unguided mortar shells cannot put the first round as close as guided ones, and requires firing several rounds, and adjusting aim, before you get one on the target. Normally, an unguided 120mm shell will land anywhere within a 136-meter circle (on the first shot). The shells that did not come close enough often hurt nearby civilians, or even friendly troops. The GPS guided shell gets it right the first time. A guided mortar round is very useful in urban warfare, where a miss will often kill civilians. The 120mm mortar round has about 2.2 kg (five pounds) of explosives, compared to 6.6 kg (15) pounds in a 155mm shell. The smaller explosive charges limits collateral damage to civilians. The GPS-guided 120mm mortar shell lands within a ten-meter (31 foot) circle. The GPS round is deemed the most useful, especially since the troops are satisfied with that degree of accuracy in GPS-guided 155mm artillery shells, 227mm GMLRS rockets and JDAM bombs.
The American Marines are developing a GPS-guided 81mm mortar shell.