M9 Gun Motor Carriage (GMC) “Sheridan” - another from the backlog, completed and posted in full.
Backstory:
Nazi Germany’s opening offensives of the Second World War and their successful employment of concentrated armoured forces in fast moving offensives had shocked US military observers. Even to armies which had previously experimented with large-scale mechanized warfare, the effects were remarkable; the collapse of Poland in 1939, followed by the defeat of the French Army and the British Expeditionary Force in France in 1940, gave rise to an impression that massed tank forces were effectively invincible when used against unprepared defenders.
Mobile armour was, however, an expensive investment. Towed anti-tank guns were cheaper and dominated most armies as a default solution for enemy tanks and became organic parts of large units like corps, divisions and regiments. Standard practice was to place these anti-tank guns at the front line, spread out to ensure full coverage. Nevertheless, experience showed that neither infantry, anti-tank guns, or tanks, when used statically could withstand the deep envelopment manoeuvres of armoured "spearheads". While some anti-tank guns or tanks could help defend the area the enemy chose to attack en masse, they could never be enough to prevent the inevitable breakthrough. Moreover, anti-tank guns were vulnerable to infantry and artillery attacks, and even attacks from the tanks they were targeting.
To counter this threat, Germany built on the already existing Sturmgeschütz ("assault gun") range of armoured vehicles. These relatively inexpensive assault guns had no turrets and were under the control of the artillery branch, and were essentially armoured artillery cannons mounted on or in a tank chassis. Originally short barrelled, these vehicles were upgraded with longer, higher velocity cannons, which made them more effective against armour without taking much away from their direct fire infantry support mission. As a result, they were used effectively against Soviet armoured thrusts on the Eastern front. Additionally, Germany also developed the Jagdpanzer ("hunting tank") range of armoured vehicles, very similar in design to assault guns but with the main purpose being the destruction of enemy armour. They could also function as mobile assault guns when required, blurring the line between the two designs.
But by the time the US entered World War II, it had neither the quality nor the quantity of armoured vehicles capable of fighting a modern war, including the ability to deal with massed armoured attacks by an enemy on a narrow front.
In April 1941, a conference focused on the future of antitank operations. The immediate effect was to create an anti-tank battalion in infantry divisions, but this organic anti-tank capacity was not deemed sufficient. The conference gave broad support to the idea of creating mobile anti-tank defensive units which could be deployed to meet an armoured attack.
The first such units were deployed during the Louisiana Manoeuvres of 1941, equipped with towed 37 mm anti-tank guns (the largest gun that could be towed by a jeep) and surplus 75 mm M1897 guns mounted on half-tracks (the M3 GMC), and again in the Carolinas manoeuvres that September. Their employment was judged a success and on 27 September, General George C. Marshall ordered the establishment of a tank destroyer Tactical and Firing Centre at Fort Hood, Texas and the activation of 53 new anti-tank battalions under the command of General Headquarters. The term "tank destroyer" was used from this point on, as it was seen as a more psychologically powerful term. On 3 December, all existing anti-tank battalions were reassigned to General Headquarters and converted to tank destroyer battalions.
In the second half of 1941, the Medium Tank M3 was the US Army’s only effective medium tank and, therefore, it was this hull that was selected for the development of a new mechanised tank destroyer. The initial design, designated 3-inch GMC T24 used the M3 hull with the turret, sponson and hull roof removed and a redundant 3” M1918 anti-aircraft gun installed. Whilst trials proved the concept, the availability of the M1918 guns was an issue as was the open-topped fighting compartment which, given the vehicle’s intended forward fighting position was deemed to be too high a risk to crew survivability. Design adjustments led to the T25 which incorporated the new 3” M7 gun (intended for the cancelled Heavy Tank M6 programme) in a fully enclosed casemate not unlike Germany’s assault guns. In early-1942, the T25 was redesignated M9 GMC and rushed into production at the Baldwin Locomotive Works.
The M9 first saw action with the British Royal Artillery in North Africa during May 1942 with mixed results. There was no questioning the 3” M7 gun’s ability to destroy German panzers from all aspects but, as a non-standard ammunition type for the British Army, logistical issues often led to M9 units running short of ammunition and, consequently, the vehicle’s tactical availability was not always all that it could be – much the same issues were experienced with the 105mm M9 Priest in UK service. As was the convention, US lend-lease armoured vehicles in British service were named after US Generals and so the M9 GMC was called after Union general Philip Sheridan. The name also transferred, unofficially, into US Army usage.
A number of US Army Sheridans were deployed to the North African theatre but by late-1942/early-1943, the M9’s design and tactical limitations were becoming increasingly at odds with the rapidly evolving Tank Destroyer Command’s doctrine. In terms of vehicle design, mobile tank destroyers were to be heavily armed, but with speed given priority over armour protection – something the M9 could just not achieve.
In the end, in much the same way that the Medium M3 was only ever intended as a compromise until the more effective Medium M4 could be produced, it was always anticipated that the M9 would also be replaced by an M4-based tank destroyer. And so, the initial combat debut of the 3” GMC M10 on 23 March 1943 at the Battle of El Guettar in North Africa effectively spelled the end of the Sheridan’s short and none too glorious career as a tank destroyer. From that point on, all remaining Sheridans in US service were relegated to the ignominy of artillery towing tractor duties.
However, that was not the end of the M9 GMC. It is of interest that a number of Sheridans in British service, having initially been the cause of such logistical headaches, remained in active duty until the end of the war in the SE Asian theatre of operations alongside their M3 sisters. These vehicles had their US 3” M7 guns replaced by the QF 17pdr and were redesignated as the 17pdr SP Ajax.
The model depicts 'Lexington', a vehicle of A company, 701st Tank Destroyer Battalion, 1st Armored Division (United States) and is made from the hull of a Tamiya M3 Grant, the tracks from a Takom M3 Grant CDL, the Barrel from a Tamiya M10 and, of course, lots of plastic/styrene card.
