M8 75mm Howitzer Motor Carriage

M8 75mm Howitzer Motor Carriage

M8 75mm Howitzer Motor Carriage

The M8 75mm Howitzer Motor Carriage was a successful attempt to mount a howitzer in the chassis of an M5 light tank, and was used in combat from late in 1943 until the end of the Second World War.

Design

Early in 1942 the Armored Force examined two alternative methods of mounting a 75mm Howitzer on the chassis of the M5 Stuart light tank. The T41 HMC had the gun mounted on a standard mount in an open topped fighting compartment. A mock-up was produced, using the correct chassis and gun but with an un-armoured superstructure, but this was abandoned in favour of the T47.

The T47 went for an alternative method of carrying the 75mm gun. The normal M5 turret was removed and a new larger open topped turret was designed. This required a larger turret ring, which in turn meant that that fighting compartment was expanded slightly. The T47 used the twin Cadillac engines of the M5 Light Tank, and also kept the suspension, final drive and gears of that vehicle.

Earlier attempts to mount a howitzer on the chassis of a light tank had all used the same method as the T41 and had failed because of a lack of space for the crew and limited protection behind the gun shields or walls of the superstructure.

A mock-up of the T47 was ready by April 1942 and went for tests at the Aberdeen Proving Ground. The open turret was found to a far superior design to the fixed fighting compartment, allowing for a fully traversable gun with a great range of elevation. It also provided greater crew protection, although the open top was a vulnerability.

The T47 was accepted for production as the M8 75mm Howitzer Motor Carriage. Cadillac built a total of 1,788 M8s between September 1942 and January 1944.

Combat

The M8 began to enter combat late in 1943 and was used in the HQ companies of tank battalions to provide fire support. The M8 was used during the Italian campaign, remaining in use into 1945. In April 1945 it was being used by the HQ Company of the 758th Tank Battalion, a segregated battalion manned by African-American troops.

The M8 was also used in Normandy and the campaign in north-western Europe. It fought in the bocage county where the open top of the turret made the crew vulnerable to small arms fire. It remained in use to the end of the war in Europe. Some took part in the fighting at Bastogne during the battle of the Bulge.

The M8 was also used in the Pacific. If was used on Saipan in June 1944, providing fire support for light tank companies. Each armoured cavalry squadron also had six M8s. They were used on Biak in July 1944 and on Leyte. In September 1944 the 81st Infantry Battalion had six M8s at the start of the invasion of Angaur in August 1944 and used the surviving vehicles on Peleliu in September-November 1944.

Some were converted to act as command vehicles. Brigadier General George Read, assistant divisional commander of the 6th Armoured Division used an M8 with the turret removed and a fixed armoured superstructure as his personal commander vehicle.

After the end of the war the M8 was quickly phased out of American service, and many were given to American allies. The French used them in Indo-China and they were part of the equipment of the South Vietnamese army. They were used in Vietnam until the early 1960s.


M8 Scott (Howitzer Motor Carriage M8)

For expediency and logistical sake during World War 2, the Americans took the chassis and hull of their M5 "Stuart" Light Tank and converted it into a Self-Propelled Howitzer (SPH) mounting the useful 75mm gun in a fully-traversing, open-topped turret to create the "Howitzer Motor Carriage M8" - also known as the "M8 General Scott" or simply "M8 Scott". Production of the Scott began in September of 1942 and ran into January of 1944 to which 1,778 units were delivered. Its operational tenure went beyond that of the United States armed forces for it saw adoption by the armies of Cambodia, France, Laos, Philippines, South Vietnam, and Taiwan for use in the post-war years - namely in Southeast Asia.

The new weapon entered testing as the "T17E1 HMC" pilot vehicle. General Motors (Cadillac Division) headed the modifications of existing Stuart vehicles for this SPH role. The revised design included some notable differences from the original M5 - chiefly in a very short-barreled main gun with thick gun mantlet found in the all-new turret. The turret roof was cut away to allow for the needed working space for the gunnery crew (as well as expelling of dangerous gasses) and the turret ring diameter increased to accommodate the new turret design. The hull roof hatches for the driver and bow machine gunner of the M5 were deleted as was the bow-mounted 0.30 caliber machine gun. The lack of hull hatches meant that the entire crew of four - driver, commander, gunner and loader - was to enter and exit the vehicle through the open-air turret. Power was from the same 2 x Cadillac gasoline dual-engine arrangement seen in the M5 Stuarts while the Vertical Volute Suspension (VVS) system was also retained. Operational ranges reached 100 miles with road speeds peaking at 36 miles per hour.

The 75mm gun was either the M2 or M3 field howitzer variant whose origins were in the classic 75mm "Pack" Howitzer M1 of 1927. In its vehicle-mounted form, this weapon became the "M2" and used the breech and gun tube of the original M1. The "M3" designation simply indicated another vehicle-mounted derivative though the recoil mechanism was now part of the gun tube itself while the barrel remained the same (and interchangeable with the M2). The vehicle allowed for stowage of 46 x 75mm projectiles and defense was provided through a trainable 0.50 caliber M2 Browning heavy machine gun over the rear face of the turret tub. This was served with a 400 x 0.50 caliber ammunition stock held aboard. Armor protection ranged from 9.5mm to 44.5mm across the various facings of the vehicle.

The M8 Scott weighed 18 tons in its finalized form. Its length was just over 16 feet with a width over 7 feet and a height of nearly 9 feet.

The M8 Scott was placed into direct enemy action during 1943, primarily against the Axis forces in the Italian Campaign where it served throughout the Allied march on Rome and then Berlin. It also proved effective in the Pacific Campaign where its 75mm far-reaching, high-explosive munitions could be brought to bear on dug-in Japanese troops with some ferocity. The M8s served in this self-propelled artillery role until supplanted by converted M4 Sherman Medium Tanks which mounted the more-powerful 105mm howitzer as well as thicker armor and a more robust drivetrain. These systems arrived from 1944 onwards and spelled the end of the M8 Scott in the long term.

Post war activity found renewed life for M8 Scotts where they were used by French Army forces in attempting to contain the situation in Indochina (during the "First Indochina War" of 1946-1954). The Scott was still in play after the French left the region for they served with the South Vietnamese Army during the upcoming Vietnam War (1955-1975). Other examples fell to neighboring Laos and Cambodia.


75mm Howitzer Motor Carriage M8 1-5

The 75mm HMC M8 was based on the light tank M5, but the front hull was modified by deletion of the drivers' hull roof hatches since the drivers had access to the vehicle through the open turret. Instead, the drivers each had a large door in the hull front plate for direct vision and two periscopes in the hull roof. The M7 howitzer mount incorporated parts of the medium tank M4's M34 gun mount. The 75mm howitzer M3 differed from the M2 by having the recoil surface and keyway machined directly onto the howitzer tube and therefore not requiring a barrel support sleeve. Both howitzers used the same breech, and a large flash suppressor was fitted around the howitzer on the M8. Late-model M8s were armed with the M3 howitzer, equipped with sandshields around the tracks, and they stored track grousers on the turret.

The mounted positions of the crew differed from the action positions listed above. For travel, the chief rode in right side of the turret, the loader occupied the .50cal ring mount, and the gunner sat in the assistant driver's position.


Armament

Armament consisted of a new open-topped turret armed with a 75 mm M2 howitzer, later a 75 mm M3 howitzer, which was a rework of the M1A1 pack howitzer. It carried 46 rounds of 75 mm ammunition types of ammunition carried were Smoke M89 and H.E. (high explosive) M48. Unlike the standard M5 Light tank, the M8 featured no hull-mounted or coaxial Browning M1919A4 .30cal machine gun. A Browning M2HB .50cal machine gun with 400 rounds was mounted on the right rear corner of the turret for local defense and anti-aircraft purposes.


World War II Database


ww2dbase Early in 1942 the US armoured force issued a requirement for a close support tank to work with medium tank battalions. To satisfy this demand the Cadillac Division of General Motors Corporation of Detroit, Michigan, United States took their M5 "Stuart VI" light tank and modified it to mount a 75mm field howitzer.

ww2dbase Cadillac's first attempt had an open-topped superstructure which resembled a scaled down M7, but the Army considered that this gave insufficient protection to the crew and, moreover, demanded too much modification of the basic tank. Eventually a new open-topped turret with full traverse, mounting the 75mm M2 howitzer was developed to fit into the turret ring of the M5 tank. Few other changes were found to be necessary beyond removing the ball-mounted hull machine-gun and transferring the driver's and co-driver's hatches to the glacis plate where they would not interfere with the traverse of the turret, and the resulting vehicle became standardized as the Howitzer Motor Carriage M8. The design was sometimes known as M8 Scott.

ww2dbase M8 production was ordered in Apr 1942, and the production numbers reached 1,778 vehicles manufactured between Sep 1942 and Jan 1944. They were issued mainly as close support vehicles in headquarters companies of American armoured battalions in Europe. They were also employed in the Pacific theatre and by the Fighting Free-French in Italy and Southern Europe.

ww2dbase Superseded (usually by 105mm howitzer-armed M4 Sherman tanks) in US formations from late 1944, the only serious defect of the M8 lay in its poor ammunition storage capacity, for which reason it was frequently fitted with a towing hook for an ammunition trailer.

ww2dbase Sources:
Ian V. Hogg & John Weeks, The Illustrated Encyclopedia of Military Vehicles (Hamlyn, 1980)
B. T. Wyite, Tanks and other Armoured Fighting Vehicles 1942-45 (Blandford Press, 1975)

Last Major Revision: Jan 2012

M8

MachineryTwo 5,670cc Cadillac Series 42 V8 petrol engines rated at 220bhp at 4000rpm
SuspensionVertical volute spring
Armament1x75mm M2 or M3 howitzer (46 rounds), 1x12.7mm .50cal Browning M2HB machine gun
Armor10-44mm
Crew4
Length4.41 m
Width2.24 m
Height2.20 m
Weight15.7 t
Speed56 km/h
Range160 km off-road 210 km on-road

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IPMS/USA Reviews

First released in 1974, the Tamiya M8 Howitzer Motor Carriage still holds up reasonably well to more modern offerings by this company, as well as some of the new folks on the block. This is one of several 1/35 scale kits that Tamiya has decided to re-release this year, and I for one certainly enjoy having another opportunity to build some of the kits that I missed out on back when they were originally released, as I had not yet picked up the armor modeling bug. A few years ago, I recall seeing a photograph of an M8 built by another modeler, and I started a search that took me a little over a year to fulfill in finding one of the original kits. That one is still on a shelf (along with a Verlinden update set), but this was a great opportunity to build what is a very well designed kit, even by today's standards.

Let me begin with some history of the real vehicle, as some may not be familiar with this particular item. The M8, also known as the "Scott" was designed based upon the chassis of the M5 Stuart light tank, and mounting an M2 75 mm howitzer. Testing of the prototype began in the spring of 1942, and production began in September at the Cadillac Division of General Motors, and when production ended in January of 1944, some 1778 M8's were delivered. The M8 carried 46 rounds of 75 mm ammunition which could include High Explosive, High Explosive Anti-Tank, and Smoke rounds. A .50 caliber machine gun was also mounted on a turret ring for close-in needs as well as anti-aircraft defense. The 34,600 pound Scott could travel at speeds of up to 36 mph, and could move approximately 100 miles on 89 gallons of gas.

I have heard that there were some issues with the dimension of the kit based upon the fact that this kit was originally designed to be motorized (as Tamiya kits typically were at the time that this was released). I have found conflicting information on the measurements of this vehicle which either has Tamiya engineers doing a very good job back in 1974, or the kit is about two feet short in length, and one and half feet short in height. The internet can be a wonderful thing at times, and at others a little frustrating with conflicting information.

Upon opening the box, the builder will find the same three sprues originally released by Tamiya, two "rubber band" style tracks, a single sheet tri-fold instruction sheet, decals for three vehicles, and two new sprues. One of the new sets of parts includes two new figures that are designed for posing in the turret, and the second is the sprue released in 1996 as the US Infantry Equipment Set. The new figures require the use of two of the helmets from the equipment set in order to finish them, but this leaves the builder plenty of additional items for this or other projects.

The plastic is molded in an olive drab color, and even though this is an older kit, there was minimal flash to clean up from the parts. As with other Tamiya kits that I have built, the model all but falls together right out of the box. My only fit issue was with the drive shaft arts A26 and 27, as their fit to the lower hull required some filler to close up the gaps. Aside from this, everything went together with just a little seam line clean-up, and no additional filler was utilized.

The decals for this release are on a single small sheet, and they are the typical Tamiya decals, which are thicker than what some companies produce, but the white is opaque, and they settle down easily with Micro Sol. I applied mine over areas that I pre-coated with Micro Gloss, and I later used Micro Flat to get my final finish. The markings are for vehicles that served on the European front, and there are also decals for a vehicle that is at Aberdeen.

I elected to build the M8 that was shown first on the directions as I wanted to use the circled stars on my howitzer motor carriage. Painting is not particularly difficult as the Scott was nearly all olive drab. The figures all went together without issue, and I think that the new ones do look a little better in their level of detail than does the original figure in the kit.

The hits of this particular kit in my opinion are the fact that I have not seen an M8 produced by any other company, so it is a one-off, and the detail in the molding includes weld seams for some of the pieces. Grab handles are all individually molded parts, and being plastic, are more three dimensional than their photo-etched counterparts. Ease of assembly is another big hit with me, and I highly recommend taking on an easier kit from time to time, just to keep the hobby "fun" as it is meant to be.

My misses for this kit are minimal as I only had one fit issue during construction (the previously mentioned drive shaft parts mating with the lower hull). Some may consider the openings in the bottom of the lower hull and "on" and "off" markings an issue, but I left them alone for this build for the nostalgia. The holes could easily be filled in with some sheet styrene and putty, and the letters could be scraped off and sanded. I did have one decal break on me (on the rear deck), but as this goes over several raised items in the area, I may have self-induced the damage when pushing on the decal with a Q-tip to remove the excess water and Micro Set. The other potential miss would be the overall dimensions of the built up vehicle, depending on which source is correct on the measurements of the real thing.

To finish the Scott I used Model Master Acryl paint for the Olive Drab, I used Aircraft Interior Black for the seats, and Metalizer Gun Metal for the machine gun. I used Vallejo paints for the rubber road wheels, tracks, and all of the figure clothing colors, and Andrea's Flesh Paint set for the heads and hands. I applied a final coat of Microscale Micro Flat as I mentioned previously for the ending overall finish.

Overall, I would highly recommend this kit to anyone wanting to add an M8 Scott to their 1/35 scale collection of armor. The kit is a pleasure to build right out of the box, and made for a nice break after some of the more challenging kits that I have recently tackled. Aside from a few small parts, this kit can be built by folks in the junior's category, and as aforementioned, can be a nice break from the challenge afforded by some of the newer kits.

My thanks to the folks at Tamiya USA for allowing the IPMS-USA to review this kit, to John Noack for allowing me to perform this assessment, and to you for taking the time to read it.

As I was finishing my review, the recent event of the major earthquake and subsequent tsunami were striking in Japan where Tamiya is based. My thoughts and prayers go out to all of the folks in that country during this time, especially for my fellow nuclear plant workers, and the challenges that they are facing.


Armament

Armament consisted of a new open-topped turret armed with a 75 mm M2 howitzer, later a 75 mm M3 howitzer, which was a rework of the M1A1 pack howitzer. It carried 46 rounds of 75 mm ammunition types of ammunition carried were Smoke M89 and H.E. (high explosive) M48. Unlike the standard M5 Light tank, the M8 featured no hull-mounted or coaxial Browning M1919A4 .30cal machine gun. A Browning M2HB .50cal machine gun with 400 rounds was mounted on the right rear corner of the turret for local defense and anti-aircraft purposes.


World War II Database


ww2dbase Early in 1942 the US armoured force issued a requirement for a close support tank to work with medium tank battalions. To satisfy this demand the Cadillac Division of General Motors Corporation of Detroit, Michigan, United States took their M5 "Stuart VI" light tank and modified it to mount a 75mm field howitzer.

ww2dbase Cadillac's first attempt had an open-topped superstructure which resembled a scaled down M7, but the Army considered that this gave insufficient protection to the crew and, moreover, demanded too much modification of the basic tank. Eventually a new open-topped turret with full traverse, mounting the 75mm M2 howitzer was developed to fit into the turret ring of the M5 tank. Few other changes were found to be necessary beyond removing the ball-mounted hull machine-gun and transferring the driver's and co-driver's hatches to the glacis plate where they would not interfere with the traverse of the turret, and the resulting vehicle became standardized as the Howitzer Motor Carriage M8. The design was sometimes known as M8 Scott.

ww2dbase M8 production was ordered in Apr 1942, and the production numbers reached 1,778 vehicles manufactured between Sep 1942 and Jan 1944. They were issued mainly as close support vehicles in headquarters companies of American armoured battalions in Europe. They were also employed in the Pacific theatre and by the Fighting Free-French in Italy and Southern Europe.

ww2dbase Superseded (usually by 105mm howitzer-armed M4 Sherman tanks) in US formations from late 1944, the only serious defect of the M8 lay in its poor ammunition storage capacity, for which reason it was frequently fitted with a towing hook for an ammunition trailer.

ww2dbase Sources:
Ian V. Hogg & John Weeks, The Illustrated Encyclopedia of Military Vehicles (Hamlyn, 1980)
B. T. Wyite, Tanks and other Armoured Fighting Vehicles 1942-45 (Blandford Press, 1975)

Last Major Revision: Jan 2012

M8

MachineryTwo 5,670cc Cadillac Series 42 V8 petrol engines rated at 220bhp at 4000rpm
SuspensionVertical volute spring
Armament1x75mm M2 or M3 howitzer (46 rounds), 1x12.7mm .50cal Browning M2HB machine gun
Armor10-44mm
Crew4
Length4.41 m
Width2.24 m
Height2.20 m
Weight15.7 t
Speed56 km/h
Range160 km off-road 210 km on-road

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M8 75mm Howitzer Motor Carriage - History

M8 Scott 75 mm Howitzer Motor Carriage

En 1941-42, les US Army tank battalions étaient divisés entre light ou medium battalions. Les premiers étaient équipés de M3/M5 light tanks et les deuxièmes de M3/M4 medium tanks. Afin de fournir un support d' artillerie mobile aux light battalions, on décida de réaliser un obusier automoteur léger. De plus, il y avait une demande d' un self-propelled 75 mm howitzer pour les infantry cannon companies.

In 1941-42, US Army tank battalions were divided between light or medium battalions. The first were equipped with M3/M5 light tanks and the second of M3/M4 medium tanks. In order to provide a mobile artillery support to the light battalions, one decided to produce a light motorized howitzer. Moreover, there was a request for a self-propelled 75 mm howitzer for the infantry cannon companies.

On tenta premièrement d' adapter le châssis du M3 light tank mais la conversion fut un échec et ce fut finalement le châssis du M5 light tank qui fut choisi. L' obusier de 75 mm était monté dans une large tourelle ouverte au dessus et équipée également d' une circulaire pour mitrailleuse de 12.7 mm antiaérienne. Le prototype T47 (ou T17E1) fut finalisé et produit par Cadillac Motor Car Division of General Motors Corp. Le T47 fut accepté pour la production en 1942 en tant que M8 75 mm Howitzer Motor Carriage.

One firstly tried to adapt the chassis of M3 light tank but conversion was a failure and it was finally the chassis of M5 light tank which was selected. The howitzer of 75 mm was assembled in a broad turret open to the top and also equipped with a circular for anti-aircraft machine-gun of 12.7 mm. The T47 prototype (or T17E1) was finalized and produced by Cadillac Motor Car Division of General Motors Corp. T47 was accepted for the production in 1942 as M8 75 mm Howitzer Motor Carriage.

Le M8 fut fabriqué par la seule Cadillac Motor car Division of General Motors Corp.

M8 was manufactured by only Cadillac Motor Car Division of General Motors Corp.

M8 HMC

Un total de 1778 exemplaires furent produits entre septembre 1942 et janvier 1944.

A total of 1778 specimens were produced between September 1942 and January 1944.