M3 GMC
Encyclopedia
The 75 mm Gun Motor Carriage M3 was a United States tank destroyer
and self-propelled artillery
piece of the Second World War
. It was the most numerous tank destroyer in U.S. Army
service, during critical battles in North Africa and the Philippines, and continued to be used in more limited numbers in Sicily, before being declared obsolete in early 1944. The GMC M3 was then used by the regimental weapons companies of Marine
regiments in 1944-45 at Saipan
, Peleliu
, and Okinawa
.
using armored divisions profoundly impressed the United States Army
. Realizing that defense against tanks was essential, an urgent requirement was issued for the development of tank destroyers for the U.S. Army. In June 1941, an M3 Halftrack was mated with an 75 mm gun M1897A4
, which was an American version of the famous "French 75" of World War I
fame. This experimental vehicle was known as the T12, and proved to work remarkably well given the speed with which it was developed. Standardized in October 1941 as the 75 mm GMC M3, over 2,200 75 mm GMC M3's were produced until April 1943. However, a large number of them were converted back to standard halftracks before issue to troop units, resulting in only 842 seeing field service. The GMC M3A1 was a variant that used a different gun mount. The 75 mm GMC M3 was reclassified first as limited standard and then as obsolete in 1944.
mounted in the rear of the halftrack. The gun had an indirect fire range of 9,200 yards (8,400 meters), and fired the AP M72 (Armor Piercing) shell that could penetrate 3.2 inches of armor at 500 yards, the APC M61 (Armor Piercing Capped) shell that could penetrate 2.8 inches of armor at 500 yards, and the HE M48 (High Explosive) shell for use against infantry and other non-armored targets. The GMC M3 carried 59 rounds of 75 mm ammunition onboard. The crewmen were equipped with a rifle and four carbines for self defense.
Confronted with an impending war with Japan
, 75 GMC M3's and T12's, termed "Self-Propelled Mount" (SPM) halftracks, were shipped to the Philippine Islands in September 1941 to form the (2nd) Provisional SPM Brigade. These vehicles saw action during the Japanese invasion of the Philippines
, and some were later captured by the Japanese and used against U.S. forces in 1944.
The GMC M3 was the most widely-deployed tank destroyer in U.S. tank destroyer battalions
during the campaign in Tunisia
in late 1942 and early 1943, and was prominent during the battles of Sidi Bou Zid
, Kasserine Pass, and El Guettar
. Although many GMC M3's were lost in these battles, the U.S. Army concluded that improper employment had caused some of these losses. The GMC M3 was again used in the tank destroyer role in the Sicilian Campaign
in July 1943. Subsequently, the GMC M3 was phased out of tank destroyer battalions and replaced by the GMC M10
, a turreted tank destroyer mounting a modern 3 inch gun. Small numbers were used for specialised tasks, such as assault guns with the Rangers of Task Force Sugar in Brittany.
Although then considered obsolete for use against German tanks, the GMC M3 was powerful enough to destroy the light tank
s deployed by the Japanese, and so the GMC M3 continued to be used in the Pacific Theater
, primarily with regimental weapons companies of the U.S. Marine Corps, seeing action on Saipan
, Peleliu
, and Okinawa
, among other island battles. Because tanks were not frequently deployed by the Japanese, the GMC M3 was often used as a self-propelled artillery piece or for direct fire support against Japanese fortifications. In 1945, the GMC M3 was replaced in Marine Corps use by the 105 mm HMC M7
self-propelled artillery piece.
in early 1943. The British deployed them in the headquarters troop
s of armored car and tank units as self-propelled artillery pieces. These, known as 75 mm SP, Autocar in British nomenclature
, were employed in Tunisia and Italy
. The 75 mm GMC M3 was also used by the French Army
on a limited basis on the Western Front 1944-45
.
Tank destroyer
A tank destroyer is a type of armored fighting vehicle armed with a gun or missile launcher, and is designed specifically to engage enemy armored vehicles...
and self-propelled artillery
Self-propelled artillery
Self-propelled artillery vehicles are combat vehicles armed with artillery. Within the term are covered self-propelled guns and rocket artillery...
piece of the Second World War
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. It was the most numerous tank destroyer in U.S. Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
service, during critical battles in North Africa and the Philippines, and continued to be used in more limited numbers in Sicily, before being declared obsolete in early 1944. The GMC M3 was then used by the regimental weapons companies of Marine
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
regiments in 1944-45 at Saipan
Battle of Saipan
The Battle of Saipan was a battle of the Pacific campaign of World War II, fought on the island of Saipan in the Mariana Islands from 15 June-9 July 1944. The Allied invasion fleet embarking the expeditionary forces left Pearl Harbor on 5 June 1944, the day before Operation Overlord in Europe was...
, Peleliu
Battle of Peleliu
The Battle of Peleliu, codenamed Operation Stalemate II, was fought between the United States and the Empire of Japan in the Pacific Theater of World War II, from September–November 1944 on the island of Peleliu, present-day Palau. U.S...
, and Okinawa
Battle of Okinawa
The Battle of Okinawa, codenamed Operation Iceberg, was fought on the Ryukyu Islands of Okinawa and was the largest amphibious assault in the Pacific War of World War II. The 82-day-long battle lasted from early April until mid-June 1945...
.
Development
The German victory over France in 1940Battle of France
In the Second World War, the Battle of France was the German invasion of France and the Low Countries, beginning on 10 May 1940, which ended the Phoney War. The battle consisted of two main operations. In the first, Fall Gelb , German armoured units pushed through the Ardennes, to cut off and...
using armored divisions profoundly impressed the United States Army
United States Army
The United States Army is the main branch of the United States Armed Forces responsible for land-based military operations. It is the largest and oldest established branch of the U.S. military, and is one of seven U.S. uniformed services...
. Realizing that defense against tanks was essential, an urgent requirement was issued for the development of tank destroyers for the U.S. Army. In June 1941, an M3 Halftrack was mated with an 75 mm gun M1897A4
Canon de 75 modèle 1897
The French 75mm field gun was a quick-firing field artillery piece adopted in March 1898. Its official French designation was: Matériel de 75mm Mle 1897. It was commonly known as the French 75, simply the 75 and Soixante-Quinze .The French 75 is widely regarded as the first modern artillery piece...
, which was an American version of the famous "French 75" of World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
fame. This experimental vehicle was known as the T12, and proved to work remarkably well given the speed with which it was developed. Standardized in October 1941 as the 75 mm GMC M3, over 2,200 75 mm GMC M3's were produced until April 1943. However, a large number of them were converted back to standard halftracks before issue to troop units, resulting in only 842 seeing field service. The GMC M3A1 was a variant that used a different gun mount. The 75 mm GMC M3 was reclassified first as limited standard and then as obsolete in 1944.
Description
The 75 mm GMC M3 was an M3 Halftrack with an M1897A4 75 mm gunCanon de 75 modèle 1897
The French 75mm field gun was a quick-firing field artillery piece adopted in March 1898. Its official French designation was: Matériel de 75mm Mle 1897. It was commonly known as the French 75, simply the 75 and Soixante-Quinze .The French 75 is widely regarded as the first modern artillery piece...
mounted in the rear of the halftrack. The gun had an indirect fire range of 9,200 yards (8,400 meters), and fired the AP M72 (Armor Piercing) shell that could penetrate 3.2 inches of armor at 500 yards, the APC M61 (Armor Piercing Capped) shell that could penetrate 2.8 inches of armor at 500 yards, and the HE M48 (High Explosive) shell for use against infantry and other non-armored targets. The GMC M3 carried 59 rounds of 75 mm ammunition onboard. The crewmen were equipped with a rifle and four carbines for self defense.
American Use
Pacific War
The Pacific War, also sometimes called the Asia-Pacific War refers broadly to the parts of World War II that took place in the Pacific Ocean, its islands, and in East Asia, then called the Far East...
, 75 GMC M3's and T12's, termed "Self-Propelled Mount" (SPM) halftracks, were shipped to the Philippine Islands in September 1941 to form the (2nd) Provisional SPM Brigade. These vehicles saw action during the Japanese invasion of the Philippines
Battle of the Philippines (1941-42)
The Philippines Campaign or the Battle of the Philippines was the invasion of the Philippines by Japan in 1941–1942 and the defense of the islands by Filipino and United States forces....
, and some were later captured by the Japanese and used against U.S. forces in 1944.
The GMC M3 was the most widely-deployed tank destroyer in U.S. tank destroyer battalions
Tank destroyer battalion (United States)
The tank destroyer battalion was a type of unit used by the United States Army during World War II. The unit was organized in one of two different forms—a towed battalion equipped with anti-tank guns, or a self-propelled battalion equipped with armored tank destroyers. U.S. Army doctrine held that...
during the campaign in Tunisia
Tunisia Campaign
The Tunisia Campaign was a series of battles that took place in Tunisia during the North African Campaign of the Second World War, between Axis and Allied forces. The Allies consisted of British Imperial Forces, including Polish and Greek contingents, with American and French corps...
in late 1942 and early 1943, and was prominent during the battles of Sidi Bou Zid
Sidi Bou Zid
Sidi Bouzid , sometimes called Sidi Bou Zid or Sīdī Bū Zayd, is a city in Tunisia and is the capital of Sidi Bouzid Governorate in the centre of the country...
, Kasserine Pass, and El Guettar
Battle of El Guettar
The Battle of El Guettar was a World War II battle that took place during the Tunisia Campaign, fought between elements of the Army Group Afrika under Jürgen von Arnim and U.S. II Corps under Lieutenant General George Patton in south-central Tunisia. It was the first battle in which U.S...
. Although many GMC M3's were lost in these battles, the U.S. Army concluded that improper employment had caused some of these losses. The GMC M3 was again used in the tank destroyer role in the Sicilian Campaign
Allied invasion of Sicily
The Allied invasion of Sicily, codenamed Operation Husky, was a major World War II campaign, in which the Allies took Sicily from the Axis . It was a large scale amphibious and airborne operation, followed by six weeks of land combat. It launched the Italian Campaign.Husky began on the night of...
in July 1943. Subsequently, the GMC M3 was phased out of tank destroyer battalions and replaced by the GMC M10
M10 Wolverine
The M10 tank destroyer, formally 3-inch Gun Motor Carriage, M10 was a United States tank destroyer of World War II based on the chassis of the M4 Sherman tank. It was numerically the most important U.S...
, a turreted tank destroyer mounting a modern 3 inch gun. Small numbers were used for specialised tasks, such as assault guns with the Rangers of Task Force Sugar in Brittany.
Although then considered obsolete for use against German tanks, the GMC M3 was powerful enough to destroy the light tank
Light tank
A light tank is a tank variant initially designed for rapid movement, and now primarily employed in low-intensity conflict. Early light tanks were generally armed and armored similar to an armored car, but used tracks in order to provide better cross-country mobility.The light tank was a major...
s deployed by the Japanese, and so the GMC M3 continued to be used in the Pacific Theater
Pacific Ocean theater of World War II
The Pacific Ocean theatre was one of four major naval theatres of war of World War II, which pitted the forces of Japan against those of the United States, the British Commonwealth, the Netherlands and France....
, primarily with regimental weapons companies of the U.S. Marine Corps, seeing action on Saipan
Battle of Saipan
The Battle of Saipan was a battle of the Pacific campaign of World War II, fought on the island of Saipan in the Mariana Islands from 15 June-9 July 1944. The Allied invasion fleet embarking the expeditionary forces left Pearl Harbor on 5 June 1944, the day before Operation Overlord in Europe was...
, Peleliu
Battle of Peleliu
The Battle of Peleliu, codenamed Operation Stalemate II, was fought between the United States and the Empire of Japan in the Pacific Theater of World War II, from September–November 1944 on the island of Peleliu, present-day Palau. U.S...
, and Okinawa
Battle of Okinawa
The Battle of Okinawa, codenamed Operation Iceberg, was fought on the Ryukyu Islands of Okinawa and was the largest amphibious assault in the Pacific War of World War II. The 82-day-long battle lasted from early April until mid-June 1945...
, among other island battles. Because tanks were not frequently deployed by the Japanese, the GMC M3 was often used as a self-propelled artillery piece or for direct fire support against Japanese fortifications. In 1945, the GMC M3 was replaced in Marine Corps use by the 105 mm HMC M7
M7 Priest
The 105 mm Howitzer Motor Carriage M7 was an American self-propelled artillery vehicle produced during World War II. It was given the official service name 105 mm Self Propelled Gun, Priest by the British Army, due to the pulpit-like machine gun ring, and following on from the Bishop and...
self-propelled artillery piece.
Allied use
Around 170 GMC M3s were provided to the British ArmyBritish Army
The British Army is the land warfare branch of Her Majesty's Armed Forces in the United Kingdom. It came into being with the unification of the Kingdom of England and Scotland into the Kingdom of Great Britain in 1707. The new British Army incorporated Regiments that had already existed in England...
in early 1943. The British deployed them in the headquarters troop
Troop
A troop is a military unit, originally a small force of cavalry, subordinate to a squadron and headed by the troop leader. In many armies a troop is the equivalent unit to the infantry section or platoon...
s of armored car and tank units as self-propelled artillery pieces. These, known as 75 mm SP, Autocar in British nomenclature
Nomenclature
Nomenclature is a term that applies to either a list of names or terms, or to the system of principles, procedures and terms related to naming - which is the assigning of a word or phrase to a particular object or property...
, were employed in Tunisia and Italy
Italian Campaign (World War II)
The Italian Campaign of World War II was the name of Allied operations in and around Italy, from 1943 to the end of the war in Europe. Joint Allied Forces Headquarters AFHQ was operationally responsible for all Allied land forces in the Mediterranean theatre, and it planned and commanded the...
. The 75 mm GMC M3 was also used by the French Army
French Army
The French Army, officially the Armée de Terre , is the land-based and largest component of the French Armed Forces.As of 2010, the army employs 123,100 regulars, 18,350 part-time reservists and 7,700 Legionnaires. All soldiers are professionals, following the suspension of conscription, voted in...
on a limited basis on the Western Front 1944-45
Western Front (World War II)
The Western Front of the European Theatre of World War II encompassed, Denmark, Norway, Luxembourg, Belgium, the Netherlands, France, and West Germany. The Western Front was marked by two phases of large-scale ground combat operations...
.