M103A1 & A2 in 35th scale - now in CAD form from Takom...
First, a nice rundown of the tanks themselves and the differences between them...
The Subject: The M103 - The last US heavy tank
Although in theory they were needed to deal with the late heavy German tanks of World War 2, the only operational tank in Europe at that time, the M26 Pershing, was not even heavy enough to fulfil its missions. This served instead as a base for the new generation of Cold War US medium tanks. However, after the end of the war, Soviet heavy tanks became the new threat as these were designed to deal with the very same tanks and now were antagonized to their former allies. The IS-3 and IS-4 series had in common a strong frontal armour, sloped and 180 mm thick, and a 122 mm gun as a standard.
The subtle exterior differences between an M103A1 & M103a2 are show in these profiles
Design
The new design was formulated in 1948-1950 at the Detroit Tank Arsenal, based on the T34 heavy tank, but shortened and made lighter to increase the power to weight ratio (14.5 tons were saved). The driver was placed in the centerline of the bow, allowing better glacis designs. Engineer Joseph William in particular, worked on a new elliptical cast hull that would save weight while being optimized at all angles for maximum sloping effectiveness, saving thickness and therefore weight. The T122 main gun was derived from an AA gun, but 15% lighter while holding a much higher chamber pressure.
M103 Heavy Tank during an exercise
It was 60 calibres long and was found capable of firing e a solid shot Armor Piercing (AP) round at 3,500 ft/sec (1066 m/sec). As designated in December 1950, the new design was to be 58 tons combat loaded, with 5 inches (127 mm) of frontal armour, mantlet being 102 mm thick, but still capable of reaching 27 mph (43 kph) with its 810 hp Chrysler V12 Av-1790. As the M103 was developed alongside the Korean War, the project was hindered by budget cuts for the war effort, as well as fresh concerns of transportation and general logistics.
Armament
The very reason behind the M103 design was its long-range 120 mm cannon capable of hitting enemy tanks at extreme range, allowing the theory of decreasing the M103's hull armour, and therefore preserving mobility. The rifled gun needed a separate-loading round, the projectile is loaded into the breech followed by its cartridge case (brass case, primer, propellant).
The turret was very large, to house the recoil mechanism and absorb its course, and cast, as the M48 and M60 turrets. It was also quite thick with 9.8 in (250 mm) on the mantlet, 11 in (280 mm) on the turret front, 3 in (76 mm) on the side and 1.5 in (38 mm) on top. The configuration was not standard, with the gunner at the right-hand side, the loader on the left-hand side, and the commander in the middle behind the gun, with his own rotatable M11 cupola (three side vision blocks, one periscope) and an adjustable seat, which was placed high in the turret bustle. The commander was also responsible for the VHS one receiver/transmitter and two separate receivers housed also in the bustle. There was a ventilation dome placed at the extreme end of the roof, behind the commander cupola to vent exhaust fumes. Of course, no NBC protection was offered.
The rounded, one-piece loader's hatch (also used by the gunner) was placed on the right-hand side, approximately half the length of the turret. Between the commander's cupola and the loader/gunner's hatch was a massive M15 rangefinder, protected by armoured glass which protruded.
The hull was made of welded cold RHA steel plates and partly cast (glacis and beak elements). The cast "beak" was 3.9-5.1 in (100 to 130 mm) at the thickest. The driver sat in the middle, with a small rounded one-piece hatch above him, and three vision blocks covering the frontal arc. He had access to two consoles, one for the basic performances indicator and another for the engine situation. The traverse motor, along with the generator and accessory box was placed in the middle, under the main gun axis.
The engine was a Continental gasoline V12 giving 750 hp (retained in the A1), coupled with a General Motors CD-850-4A or -4B transmission, with a 2 ranges forward, 1 reverse speed gearbox. Due to the weight to displace, top speed was not impressive, barely 30 kph on flat, which fall rapidly cross-country and an equally limited range of 80 miles at best (130 km) when cruising.
A makeshift stairway to the tank deck while on the range...
The issue was solved with the adoption (with little change) of the M60 diesel engine in the 1960s which increased performances (23 mph or 37 kph), and range (295 miles or 480 km) of the tank for an average of 280 US gallons (710 litres). The power was passed onto the rear-drive sprockets, seven road wheels, and no less than six heavenly spaced return rollers. The tracks, suspensions units (torsion arms) return rollers, idler, drive sprockets, were of the standardized type also used by the M48-M60. In addition to the torsion arms, shock absorbers with dampers were installed on the first three front and two rear suspension units.
Tank, Combat, Full-Tracked, 120-mm Gun, M103A1:
M103A1 - a modified variant of the T43E1 for the USMC, a new rangefinder and ballistic computer, electric rotation of the turret; 219 conversions made in 1959. By May 1957, the M103A1 standard was set up for the US Army. In November / December, the United States Marine Corps (USMC) addressed a memorandum for a comprehensive modernization of the M103A1 which would end in 1960. 3 M103A1 pilot models were then standardized to the M103A2, totalling 156 in service. Later a second batch of 52 would enter service with the USMC totalling 208.
A Marine M103A1 on American-Spanish naval exercises, October 1964
A Marine Corps M103A1 over watches infantry in the distance on manoeuvres at Camp Pendleton, California. Camouflage seems senseless for such a large machine...
By January 1959, 220 vehicles were standardized after modifications for the USMC as the M103A1, and the US Army requested 72 tanks from the USMC stocks, that were sent in Europe and attached to the 899th heavy tank battalion of the 7th US Army (Brethren, Germany). This unit was renamed later 2d Battalion, 33d Armor, and comprised four tank companies of six platoons (of three) each.
In Germany, a single Army battalion of 72 M103 tanks operated in general support of the medium tank battalions of the Seventh Army. This M103 of the 2-33rd (120mm) Tank Battalion shows the rear rack used by the Army to hold four jettisonable 55-gallon fuel drums, fitted to both medium and heavy tanks because of the short-range obtained with their gasoline engines.
In 1963, they were handed back to the USMC. The latter needed an evolved version, which was obtained by upgrading the existing M103A1 to the M60 standard, giving the M103A2.
The M103A2 were a real improvement with a more powerful diesel engine, better top speed, and moreover far better range. Now the battalions "had legs". These were seen largely as a stopgap measure before the arrival of the MBT-70. These tanks never left the soil of the USA until 1972, when they were declared obsolete and gradually retired from service. In practice, these were replaced by M60s that have a lighter gun, but capable of greater range and better performances overall. The M103 was the last American heavy tank in inventory, and 25 are preserved to this day in many locations in the USA, and a single one at Bovington (UK).
Tank, Combat, Full-Tracked, 120-mm Gun, M103A2:
M103A2 - upgrading M103A1 on the standard coming out of the M60, diesel engine, new range finder; 153 conversions made in 1964.
M103A2 - upgrading M103A1 on the standard coming out of the M60, diesel engine, new range finder; 153 conversions made in 1964.
The M103A2 was the last upgraded version largely to the M60 standard (153 converted), with New 750 hp (559 kW) diesel engine, providing better range and top speed, and the M24 Coincidence Rangefinder replacing the old stereoscopic rangefinder. Used exclusively by the USMC.
The two new kits in CAD from Takom:
M103 A1
From Takom
Kit No#2139
1/35th scale
Plastic injection moulded kit - new tool.
Metal Barrel.
Workable tracks.
Hatches open and close.
Photo-etch included.
The A1 variant features an all new hull, with new road wheels and suspension parts, the escape hatch under the hull is a new part. The tracks are made up of seven parts each, but are workable on the moving suspension to add some variety and depth to the completed kit's look.
There is a metal barrel included with the kit (nice) and the whole fenders, under turret and mantlet cover is new.M103 A2
From Takom
Kit No#2140
1/35th scale
Plastic injection moulded kit - new tool.
Metal Barrel.
Workable tracks.
Workable suspension.
Hatches open and close.
Photo-etch included.
A little like the A1, this M103 A2 kit features the new turned metal barrel. The infra-red, and under turret rear section is all-new.
The multi-part tracks look quite a construction, but they are workable, along with the suspension again, and the escape hatch under the hull is all-new again. The major difference of that whole new engine deck is apparent here.
The kit should be released to the public in just under a months time if regular patterns are followed in releases.
For more on this kit and all of Takom's other models, look at their Website