M30 mortar#References

{{Infobox weapon

| name = M30

| image = M30 mortar schematic.gif

| image_size = 300

| caption =

| origin = United States

| type = Mortar

| is_ranged = yes

| is_artillery = yes

| service = 1951–Present

| used_by = See Users

| wars = Korean War
Cambodian Civil War
Laotian Civil War
Vietnam War
Portuguese Colonial War
Third Indochina War
Sino-Vietnamese War
Lebanese Civil War
Guatemalan Civil War
Gulf War

| designer = U.S. Chemical Warfare Service

| design_date =

| manufacturer =

| unit_cost =

| production_date =

| number =

| variants =

| spec_label =

| weight = 305 kg (672.25 lb)

| length ={{convert|1.524|m|ft|abbr=on|sigfig=1}}

| part_length =

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| crew =

| cartridge =

| cartridge_weight =

| caliber = 106.7 mm (4.2 in)

| barrels =

| action =

| rate = 18 rpm max., 3 rpm sustained

| velocity =

| range = 770 m to 6,840 m
(840 yd to 7,480 yd)

| max_range = 6,840 m (7,480 yd)

| feed =

| sights =

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}}

The M30 106.7 mm (4.2 inch, or "Four-deuce") heavy mortar is an American rifled, muzzle-loading, high-angle-of-fire weapon used for long-range indirect fire support to infantry units.

Design

File:M30 mortar at the War Remnants Museum.jpg]]

The M30 system weighs {{convert|305|kg|lb}} including the complete mortar with a welded steel rotator, M24A1 base plate, and M53 sight.

A point of interest in the design of this mortar is the rifled barrel. A rifled barrel requires the round to be a very tight fit to the bore in order for the rifling to engage the round and impart rotation to it. But, in a muzzle-loading mortar, the round has to be loose enough in the bore to drop in from the front. In order to have it both ways, these rounds have an expandable ring at the base, which expands into the rifling under the pressure of the firing charge that propels the round. Additionally, imparting a spin to a round causes it to drift away from the direction of fire during flight and the longer the flight (greater range to target), the farther the drift, so the computation for setting the direction for firing at a specific target has to account for this drift.

American rounds are designed to be both drop-safe and bore-safe. That is, the fuzes in the rounds for this rifled mortar are only armed once the round had spun a certain number of times, meaning that the round is not armed until it has exited the barrel spinning and has traveled a safe distance from the mortar emplacement.

= Types of rounds =

  • HE M329A1—max range {{convert|5650|m|yd}}, weight {{convert|27.07|lb}}
  • HE M329A2—max range {{convert|6840|m|yd}}, weight {{convert|22|lb|kg}}
  • WP M328A1—max range {{convert|5650|m|yd}}
  • ILLUM M335A1—max range {{convert|5290|m|yd}}, 70-second burn time @ 500,000 candlepower
  • ILLUM M335A2—max range {{convert|5490|m|yd}}, 90-second burn time @ 850,000 candlepower

ILLUM is illumination, a parachute flare round with fixed timed detonation. Deployment height above ground is determined by gun elevation angle and propelling charge.

HE (high-explosive) and WP (white phosphorus) rounds could be fitted with various fuses before firing, including a proximity fuse set for detonation at about {{convert|30|ft|m|abbr=on}} above ground to maximize the affected target area and to spray shrapnel down into foxholes.

There was also a sub-caliber training device that utilized blank 20-gauge shotgun shells to propel an inert training round several hundred meters. This training was for the gunnery skill of laying (in a sense, aiming) the guns. This device had originally been developed during WWII for the M2 mortar.

History

The M30 entered service with the U.S. Army in 1951, replacing the previous M2 106.7 mm mortar.[http://www.rt66.com/~korteng/SmallArms/4pt2.htm 4.2 inch M30 Mortar] {{webarchive|url=https://web.archive.org/web/20070710065804/http://www.rt66.com/~korteng/SmallArms/4pt2.htm |date=2007-07-10 }}. Rt66.com It was adopted due to the extended range and lethality in comparison to the previous M2 mortar, although the M30, at {{convert|305|kg|lb}}, was significantly heavier than the {{convert|151|kg|lb}} M2.

Due to this heavy weight, the mortar was most often mounted in a tracked mortar carrier of the M113 family, designated as the M106 mortar carrier. This vehicle mounted mortar was crewed by five people: the track commander (mortar sergeant/gun commander), gunner, assistant gunner, ammunition bearer and vehicle driver. Ground mounting of the mortar was time consuming and strenuous as a hole had to be dug for the base plate of the mortar to rest in, sandbags had to filled and placed around the base plate to stabilize it and to protect the exposed ammunition. Also, this decreased the accuracy of the weapon as the recoil from firing caused the base plate to shift in the ground. This movement also made the crew have to "lay" the gun back on the aiming stakes more often, causing a temporary lack of fire while the weapon was repositioned and re-sighted back to its original reference point.{{cn|date=March 2019}}

During the Vietnam War, both the US Marine Corps and the US Army deployed the M30 mortar.{{cite book|title=The US Army in the Vietnam War 1965–73|url=https://books.google.com/books?id=AVeICwAAQBAJ|series=Battle Orders 33|first= Gordon L. |last=Rottman|date=2 Apr 2008|isbn=9781846032394|publisher=Osprey Publishing|page=56}}{{cite book|title= The US Marine Corps in the Vietnam War: III Marine Amphibious Force 1965–75|series= Battle Orders 19|first= Ed|last= Gilbert |date= 1 Jun 2006|isbn= 9781841769875 |publisher= Osprey Publishing|pages=68–69}} The USMC mounted the M30 mortar on the carriage of the M116 howitzer, this assembly being known as the M98 Howtar. The Saudi Arabian Army deployed the M30 in 1990-1991 during the Gulf War.{{cite book|title=Armies of the Gulf War|series= Elite 45 |first= Gordon L.|last= Rottman|date=1993|isbn= 9781855322776|publisher=Osprey Publishing|page=30}} The M30 was also used in Bosnia during Operation Joint Endeavor in 1996.{{Cite web|url=https://nara.getarchive.net/media/on-the-afternoon-of-may-21st-1996-two-soldiers-from-the-mortar-platoon-4th-d900cc|title = On the afternoon of May 21st, 1996, two soldiers from the Mortar Platoon, 4th Battalion, 12th Mechanized Infantry, do some fine tuning to their M-30, 107mm, Heavy Mortar during a live fire exercise in Glamoc, Bosnia-Herzegovina (XJ 641 886) in support of Operation Joint Endeavor|date = 21 May 1996}}

Users

{{div col}}

  • {{flag|Austria}}
  • {{flag|Belgium}}{{cite book|title=The armies of the NATO nations: Organization, concept of war, weapons and equipment|series=Truppendienst Handbooks Volume 3|year= 1987|first=Friedrich |last=Wiener |page=470|publisher=Herold Publishers|location=Vienna}}{{cite encyclopedia|title=107 mm M30 rifled mortar|encyclopedia=Jane's Infantry Weapons 2002-2003|url=https://archive.org/details/Janes_Infantry_Weapons/page/n5323|pages=5324–5325|date=4 June 2001|first1=Terry J.|last1=Gander|first2=Charles Q.|last2=Cutshaw}}
  • {{flag|Bolivia}}{{cite encyclopedia|title=National inventories, Bolivia|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n949|page=949|date=22 November 2000|first1=Terry J.|last1=Gander}}{{sfn|The Military Balance 2016|p=380}}
  • {{BRA}}{{cite encyclopedia|title=National inventories, Brazil|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n1031|page=1031|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{flag|Cambodia}}
  • {{flag|Canada}}
  • {{flag|Colombia}}{{cite encyclopedia|title=National inventories, Colombia|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n1601|page=1601|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{DRC}}
  • {{CYP}}: less than 20 {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|p=85}}
  • {{DOM}}: 4 {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|p=394}}
  • {{flag|Ecuador}}{{cite encyclopedia|title=National inventories, Ecuador|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n1602|page=1602|date=22 November 2000|first1=Terry J.|last1=Gander}}{{sfn|The Military Balance 2016|p=396}}
  • {{flag|Ethiopia}}{{cite encyclopedia|title=National inventories, Ethiopia|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n1645|page=1645|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{flag|Greece}}: 620 (including 231 on vehicles) in service in the Hellenic Army {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|p=104}}
  • {{flag|Guatemala}}: 12 from Israel, in store {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|p=199}}
  • {{IRN}}{{sfn|The Military Balance 2016|p=328}}
  • {{ISR}}: 50 {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|p=337}}
  • {{flag|Italy}}
  • {{JAP}}{{cite encyclopedia|title=National inventories, Japan|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n3010|page=3010|date=22 November 2000|first=Terry J.|last=Gander}}
  • {{flag|Jordan}}{{cite encyclopedia|title=National inventories, Jordan|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n3014|page=3014|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{ROK}}{{sfn|The Military Balance 2016|p=267}}
  • {{KWT}}: 6 {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|p=339}}
  • {{flag|Lebanon}}
  • {{flag|Liberia}}
  • {{flag|Libya}}{{cite encyclopedia|title=National inventories, Libya|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n3091|page=3091|date=22 November 2000|first=Terry J.|last=Gander}}
  • {{MEX}}{{cite encyclopedia|title=National inventories, Mexico|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n3105|page=3105|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{flag|Nepal}}{{cite encyclopedia|title=National inventories, Nepal|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n3113|page=3113|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{flag|Netherlands}}
  • {{flag|Norway}}
  • {{flag|Oman}}: 20 {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|p=347}}
  • {{flag|Paraguay}}{{cite encyclopedia|title=National inventories, Paraguay|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n3240|page=3240|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{flag|Philippines}}:{{cite encyclopedia|title=National inventories, Philippines|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n3269|page=3269|date=22 November 2000|first1=Terry J.|last1=Gander}} 40 in the Philippine Army and some in the Philippine Marine Corps {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|pp=284-285}}
  • {{flag|Portugal}}:{{cite encyclopedia|title=National inventories, Portugal|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n3371|page=3371|date=22 November 2000|first1=Terry J.|last1=Gander}} 30 (including 20 on vehicles) in service {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|p=130}}
  • {{flag|Saudi Arabia}}: ~150 in service with the Saudi Arabian Army {{as of|lc=yes|2016}}, some used on vehicles{{sfn|The Military Balance 2016|p=351}}{{cite encyclopedia|title=National inventories, Saudi Arabia|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n3849|page=3850|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{flag|Taiwan}}{{cite encyclopedia|title=National inventories, Taiwan|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n4551|page=4552|date=22 November 2000|first1=Terry J.|last1=Gander}}{{sfn|The Military Balance 2016|p=291}}
  • {{flag|Tunisia}}{{cite encyclopedia|title=National inventories, Tunisia|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n4572|page=4572|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{flag|Turkey}}: 1,264 {{as of|lc=yes|2016}}{{sfn|The Military Balance 2016|p=148}}
  • {{flag|United States}}: US Army{{sfn|Rottman|2010|p=35}} and US National Guard
  • {{flag|Uruguay}}{{cite encyclopedia|title=National inventories, Uruguay|encyclopedia=Jane's Infantry Weapons 2001-2002|url=https://archive.org/details/Janes_Infantry_Weapons/page/n5797|page=5797|date=22 November 2000|first1=Terry J.|last1=Gander}}
  • {{flag|South Vietnam}}{{cite book|title=Army of the Republic of Vietnam 1955–75|publisher=Osprey Publishing|first=Gordon L. |last=Rottman|series=Men at Arms 458 |date=2010|page=9|isbn=9781849081818}}

{{div col end}}

References

=Citations=

{{Reflist|25em}}

=Sources=

{{refbegin}}

  • {{cite book|title=The Military Balance 2016|date=February 2016|volume=116|isbn=9781857438352 |publisher=Routlegde|ref={{harvid|The Military Balance 2016}}|author=International Institute for Strategic Studies|author-link=International Institute for Strategic Studies}}

{{refend}}

See also