St Chamond Self-Propelled Guns
by Charlie Clelland

St Chamond SPG 9

Self-Propelled Guns (SPGs) are usually associated with WW2 but the history of SPGs stretches back to WW1. One of the conclusions of the French High Command analysing the failed offensives of 1915 was that artillery could not be brought up in support of attacking infantry fast enough to prevent counter-attacks pushing back the attacking forces. Although using tracked towing vehicles for heavy artillery was feasible, shown by trials with Holt tractors, there were delays in setting up the guns even when delivered to suitable firing positions. Ideally a vehicle was required which could traverse the churned up landscape of the trenches and fire from the vehicle. Wheeled vehicles could not traverse the shell cratered landscape and were limited in the size of gun which could be carried and fired from the vehicle.

Much of the information in English on the St Chamond SPGs is incomplete and often in error so this article relies on articles in French published in Historie de Guerre, Blindés & Materiel.


120 L Rimailho SPG

The French Army asked the FAMH (St Chamond) organisation to study the problem. St Chamond's technical director Col. Emile Rimailho designed a vehicle based on the St Chamond tank chassis with a 120mm St Chamond gun mounted at the rear of the chassis. The vehicle was tested in 1917. Very little data seems to be available on this vehicle but it appears that the sprung suspension of the St Chamond tank was simplified to rigid by bolting the Holt bogie frames to the hull sides. Although this vehicle appears to have met the basic requirements it was a development dead end since the gun was hardly larger than existing field guns and the gun type had not been accepted for the French Army. The French Ministry of Munitions was also of the view that, given the expense of the St Chamond vehicle, as large a gun as possible should be mounted.


St Chamond SPG 18

St Chamond SPG redesign

The exact reasoning that Rimailho and his team used to arrive at the next SPG design has not been recorded but it can be reconstructed to some extent. Ideally an SPG should carry as large a gun as practicable since this means it can destroy any strongpoints holding up an advance and from a range that keeps the vehicle away from local anti-tank defences. Also a large calibre gun can add significantly to the weight of artillery fire in the initial bombardment before an attack. However, a large, heavy gun meant that the vehicle would only be able to carry a small amount of ammunition or be dependent on a separate munitions vehicle for its ammunition supply. The solution arrived at was quite ingenious - use two vehicles: one to carry ammunition and the gun crew and the other to carry the gun. Because the St Chamond chassis was powered by a petrol-electric system the gun carrier did not have to have an engine and generator but could be powered from the tractor vehicle by an electrical cable. Since the engine and generator were no longer necessary the centre of the chassis could be opened out so the gun could recoil below the deck level which meant the gun could be mounted lower in the chassis and improve the stability of the gun vehicle. Since the St Chamond had two electric motors which could independently drive each track the vehicle could "turn in place" which meant the mounted gun didn't need traversing gear which in turn allowed for (notionally) even larger guns to be mounted without destabilising the carrier vehicle.


St Chamond SPG tractor

The tractor unit of the St Chamond SPG was much the same across all the various models of SPG. The main difference between the SPG version tractors were the shell racks at the rear of the tractor. The power train was similar to the St Chamond tank with a Panhard petrol engine of 120 h.p. coupled to the Crochat-Collardeau transmission with an external 50m power cable fed power to the gun vehicle. When travelling on roads a 2m steel drawbar was used to link the tractor and gun vehicle, off road the two vehicles were only linked by the power cable. At the rear of the tractor was a small crane to lift shells onto the tractor and also transfer shells to the gun vehicle. The crane details are a little different between the different SPGs. The tractors were also equipped with a hoist at the rear of the vehicle to lift shells up to the deck level.


St Chamond SPG 19 St Chamond SPG 20 St Chamond SPG 21

Obusier 220mm de St Chamond sur affût-chenilles St Chamond

The 1917 version of the 220mm St Chamond howitzer could fire a 100kg projectile at a muzzle velocity of 500 m/sec giving a max. range of 13,500m. The 1918 version was even better with a longer barrel giving a muzzle velocity of 560 m/sec and a max. range of 15,000m. However, it was not adopted by the French Army since the war ended before production could start.

The prototype of the 220mm howitzer SPG was initially equipped with wheels as well as tracks. The double rear wheels were intended to be attached to extensions of the drive sprockets and the pair of wheels at the front of the vehicle were attached to frame which was normally swung to one side. It was found that changing from tracks to wheels was not a simple exercise and although the wheels meant that road surfaces weren't damaged by the tracks it was too difficult and time consuming. The gun vehicle was also too wide with the wheels fitted. The 220mm howitzer SPG was the only one fitted with wheel conversion.

The gun mount was a dual system which used the hydro-pneumatic recoil/recuperator of the gun combined with inclined rails somewhat like the Vavasseur gun mount of the 1880s. The gun was attached to a trolley which ran on the inclined rails. The trolley was also equipped with brakes so the gun trolley was slowed when it returned to the battery position after firing. The gun was designed to fire over the rear of the vehicle. There are 4 jacks on the gun vehicle, whether these were used to stabilise the gun vehicle before firing is not known.

For transport the barrel was lowered to 0° and the trolley moved up to the fully forward position - there is a rack and pinion gear on the surviving 194mm SPG which looks as if it was used to pull the gun towards the front of the gun vehicle. There are a pair of large handwheels attached to chassis sides which connected to the vehicle drive via a gearbox, they were used for fine gun traverse movements. Where large traverse movements were required the vehicle would be turned with the electric drive.

The 220mm SPG was tested without the howitzer with a ballast weight representing the gun in January 1918. The 220mm howitzer was eventually fitted and tested at the St Chamond proving ground in April 1918. It was delivered to the French Army testing centre at Bourges in May 1918. The initial testing was satisfactory so it was deployed north of Verdun in July 1918 for operational trials. This was the only time the St Chamond SPGs were used in operations during WW1. Evaluation by the army was quite enthusiastic, noting the SPG could achieve 2.5 km/hr and although the corners of roads were damaged by the tracks and crossing bridges required more study the performance of the SPG was "already remarkable". General Foch, commander in chief, demanded the construction of 75 220mm SPGs in Sept 1918. No production 220mm howitzer vehicles were completed before the Armistice in Nov 1918 when the order for these vehicles was cancelled.

Data
Calibre220mm
Vehicle Length6.53m
Vehicle Height2.54m (gun in travel position)
Vehicle Weight24,000kg
Elevation+0° to +60°
Traverse360° (vehicle traverse)
Muzzle Velocity500 m/sec (Mle 1917)
Max. Range13,500m
Shell Weight100 kg
Rate of Fire2 Rounds/min


St Chamond SPG 22 St Chamond SPG 23 St Chamond SPG 24 St Chamond SPG 25 St Chamond SPG 26

Mortier 280mm TR de Schneider sur affût-chenilles St Chamond

The 280mm Schneider howitzer is discussed in another article on Landships II here.

The adaptation of the 280mm TR Schneider howitzer to the St Chamond chassis was part of a project to place the heaviest guns on tracked chassis to improve their mobility (4). St Chamond reported that the design was under way in March 1918. On March 2nd 25 SPGs with the 280mm Schneider howitzer were ordered. Given the weight and size of the Schneider howitzer barrel additional structure was required to balance the gun during firing. An air brake was also used to slow the howitzer's return to battery position when it rolled down the inclined rails. In October 1918 St Chamond projected that the first 280mm SPGs would be delivered in April 1919. All 25 ordered 280mm SPGs were delivered in 1919 and appear to have been immediately placed in reserve.

The swinging foot which originally was used for the removable front wheels on the St Chamond chassis was recycled as the support for a large circular earth plate to stabilise the gun vehicle during firing. The charging trolley of the platform mounted 280mm howitzer was retained and the front of the gun vehicle was extended to accomodate the rails for the charging trolley.


Data
Calibre279.4mm L/12
Vehicle Length7.46m
Vehicle Height2.54m (gun in travel position)
Vehicle Weight28,000kg
Vehicle Speed5 km/hr (roads) 2 - 5km.hr (off road)
Elevation+10° to +60°
Traverse360° (vehicle traverse)
Traverse time360° in 15 - 20 secs
Muzzle Velocity418 m/sec
Max. Range10,950m
Shell Weight203 - 275 kg
Rate of Fire2.5 Rounds/min


St Chamond SPG 27 St Chamond SPG 28 St Chamond SPG 29 St Chamond SPG 30 St Chamond SPG 31

Canon 194mm GPF sur affût-chenilles St Chamond

The 194mm GPF gun was a development by Filloux to utilise the large stocks of 194mm ammunition available in French Naval Arsenals. The 194mm (or 19cm) guns were used as secondary guns on pre-dreadnought battleships and the main guns on protected cruisers - both of these classes of warships were obsolete by WW1 but large holdings of ammunition remained. The 194mm GPF gun used the same carriage as the 155mm GPF although it was somewhat heavier at 16,000kg which meant it was transported as two components - barrel plus carriage. The max. range of the 194mm GPF was 18,000m with an 83.5kg projectile and the max. rate of fire was 2 rounds/min. Filloux proposed in 1917 to have the first 194mm gun in testing by April 1918. It was intended to initially equip a regiment (36 guns) with towed 194mm pieces and the whole program was to create 200 gun tubes, 150 on towed carriages and 50 on the St Chamond SPG chassis. Delays in production meant that none of the towed 194mm guns were complete at the time of the Armistice. The program was reduced to 100 gun tubes which were all to be used on the 50 St Chamond chassis. No towed 194mm guns entered service with the French Army1.

St Chamond began investigating adapting the 194mm GPF to the St Chamond chassis in February 1918, 50 194mm SPGs were ordered on March 2, 1918. No 194mm SPGs were completed before the Armistice and the 50 SPGs were delivered in the second half of 1919.

Data
Calibre194.4mm L/33.5
Vehicle Length7.755m
Vehicle Height2.54m (gun in travel position)
Vehicle Weight29,600kg
Elevation0° to +40°
Traverse360° (vehicle traverse)
Muzzle Velocity725 m/sec
Max. Range20,800m
Shell Weight78.83kg (Mle 1921 AGP), 84.88kg (Mle 1920 FAGP)
Rate of Fire1 Rounds/min


St Chamond SPG 32

Canon 155mm GPF sur affût chenilles St Chamond

The 155mm GPF gun is discussed in another article on Landships II here.

Mechanisation options for the 155mm GPF gun were explored in the early part of 1918. One, fairly obvious, option was to mount the gun on a St Chamond chassis. The Commander in Chief of the Army asked the Minister of Armaments in September 1918 for 130 155mm GPF SPGs. The first prototype SPG was not completed before the Armistice when the order was cancelled. The sole 155mm GPF SPG was completed early in 1919.


St Chamond SPG 33

Caterpillar Mark IV and IVA 240mm SPG

The US Army had no heavy artillery at the time the USA entered WW1 in 1917. However, the US Army was determined to "catch up" with other armies and very quickly acquired licences to build the French 155mm GPF, 280mm (240mm) TR Schneider and British 8inch howitzer. There seems to be very little accessible documentation on the US Army heavy artillery but it is reasonably clear the US Army was following the British and French advances in mechanising artillery. It appears that the US Army Ordnance Dept commissioned the building of a tractor and gun vehicle by the Rock Island Arsenal in 1918 based on St Chamond drawings of the 280mm armed vehicle modified for the 240mm howitzer barrel. The Mark IVA had a 150 hp 6-cylinder Van Blerk engine driving a 70 kW 400V General Electric generator - this reportedly gave a maximum speed of 9 mph (14 kph). The loading trolley on the St Chamond 280mm SPG was replaced by a crane was installed on the gun vehicle to lift the shells directly to the loading tray of the gun from the tractor. The vehicles were designated Mark IV (the gun vehicle) and Mark IVA (the tractor) and were tested at Aberdeen, MD in 1920-21.

The results of the US Army's evaluation of the Mark IV are unknown. The US did not pursue SPGs after about 1923 in part due to financial constraints on the Army and the conclusion of the Artillery Board that "self-propelled guns offered no advantages over towed guns".

Images are from the site tankhistory.com.

St Chamond SPG 1 St Chamond SPG 2 St Chamond SPG 3 St Chamond SPG 4

Service after WW1

The 25 280mm and 50 194mm GPF armed SPGs delivered in 1919 were incorporated into a unit eventually known as 184 RALT (Regiment de Artillerie Lourdes à Tracteur) at Valence. This unit seems to have keep the St Chamond SPGs as a "force in being" between the wars, maintaining and preserving them as well as running training courses to ensure a pool of trained gunners and operators. French Army evaluations of the St Chamond SPGs between the wars were not positive complaining of the low speed of the SPGs and the damage the tracked vehicles did to the roads. The St Chamond SPGs were mobilised at the start of WW2, but, because of their low speeds saw little, if any action during the German invasion of France in 1940. Many of the SPGs were destroyed by retreating French troops when the SPGs couldn't be evacuated due to the speed of the German advance.2

However, the St Chamond SPGs were used in propaganda film clips shot in May 1940.3

194mm St Chamond Deploying
194mm St Chamonds Firing
280mm St Chamonds Deploying and Firing

These show St Chamond 194mm GPF SPGs deploying although it should be noted the gun vehicle is being driven in reverse in one segment presumably to look more menacing. In the other clip with the batteries firing it should be noted that using the jacks and plate to hold the hull still during firing seems to have been abandoned by 1940 and the gun vehicle is allowed to roll back about 2m on firing, presumably it is driven back to the firing line.

The Wehrmacht used captured St Chamond SPGs in small numbers in Russia, Italy and France as the 19.4cm Kanone 458(f) auf Selbstfahrrlafette . At least 3 194mm SPGs were on strength with the 84th Heer Artillery Regiment, part of Army Group North in front of Leningrad in 1942. The SPGs seem to have been used as heavy artillery with limited self-mobility. Many of the extant images of St Chamond SPGs were taken during Wehrmacht service. The 280mm howitzer armed SPG does not seem to have been used by the Wehrmacht possibly because so few were intact after the French Army retreat in 1940.


St Chamond SPG 34
194mm SPG abandoned in Italy
St Chamond SPG 35
194mm SPG in Wehrmacht service Russian front
St Chamond SPG 36
280mm SPGs found in Russelheim, Germany, April 1945. Note the barrels are missing and the original French markings are still visible.

Survivors

There are two surviving gun vehicles, no tractors appear to have survived.

The collection at Aberdeen has a 194mm GPF gun vehicle. This was, according to the plaque beside the vehicle, captured in a Wehrmacht vehicle park outside Paris in 1944. The vehicle was transported back to the US and has been displayed outside at Aberdeen until recently. . The vehicle was generally in poor condition, the floor had rusted away and a number of other components had been mostly destroyed by neglect. The images are from a set taken by Seth Gaines in 2008 at Aberdeen, Seth has allowed us to use his images for this article. The 194mm GPF SPG is now at Fort Sill, Oklahoma and is being restored.

St Chamond SPG 5 St Chamond SPG 6 St Chamond SPG 7 St Chamond SPG 8 St Chamond SPG 10 St Chamond SPG 11 St Chamond SPG 12

St Chamond SPG 37
St Chamond 194mm SPG at Fort Sill undergoing restoration with rust inhibitor coat - image by James Pavelka

A few years ago another St Chamond SPG gun vehicle was found buried outside Hannover, Germany. This was a 280mm Schneider howitzer armed vehicle. The vehicle has been reassembled and is at the Bundeswehr Military History Museum, Dresden.

St Chamond SPG 38 St Chamond SPG 39 St Chamond SPG 40 St Chamond SPG 41 St Chamond SPG 42 St Chamond SPG 43

Images courtesy of Georg Kaminski (first 2) and Ferdinand Hegl (remainder)


Notes
  1. It was Filloux's intent to machine worn 155mm GPF barrels to 164mm calibre to utilise another calibre of obsolete Naval ammunition.
  2. The fate of the 280mm Schneider SPGs is documented in J-Y Mary "1939-1940 Le Rendez-Vous Manque Des 280 sur Chenilles" Histoire de Guerre Blindés & Materiel Nov-Dec 2006, No. 74, pp.36-39.
  3. Thanks to "James H" of the Landships forum for finding the British Pathé 194mm Saint-Chamond SPG clips

Sources

The primary information for this article came from:

François Vauvillier "La Formidable Artillerie à Chenilles du Colonel Rimailho - I - Les Pièces Courtes" in "Histoire de Guerre Blindés & Materiel" No. 74, Nov-Dec 2006, pp.26-35.
François Vauvillier "La Formidable Artillerie à Chenilles du Colonel Rimailho - II - Les Pièces Longes" in "Histoire de Guerre Blindés & Materiel" No. 75, Fév-Mars 2007, pp.68-75.


More Information

Tankette 4/35, 5/35, and Steel Masters no.41 octobre-novembre 2000 have articles, including plans, of the St Chamond SPG.


How to Model this Gun

Retrokits makes an excellent 1/72 scale kit, that includes the Ammo Vehicle.
Convoy makes a fine 1/76 scale resin kit of this artillery piece (and of the ammo carrier) - see Kit Reviews section.