Semovente M43 da 105/25

Kingdom of Italy (1943-1945)
Self-Propelled Gun – 121 Built

The Semovente FIAT-Ansaldo M43 da 105/25 was an Italian self-propelled gun developed by FIAT and Ansaldo. It was based on the M42 da 75/18 and used in limited numbers by the Regio Esercito (Eng. Italian Royal Army) before the armistice of 8th September 1943. After the armistice of Cassibile and the occupation of the center and northern parts of Italy by the Germans, the Semoventi were captured and used by the German Army and by the new Italian Collaborationist Army.

Development

After the entry into service of the Semoventi (singular Semovente) armed with 75 mm L/18 cannons, based on the chassis of the tanks of the ‘M’ series (Medi, Eng. Medium), the M13/40 and M14/41, it was found that the vehicles were adequate for infantry support and anti-tank vehicles. However, the Regio Esercito needed something more heavily armed and armored to be able to fight against the more modern vehicles put into service by the Allies. By this point, the Italians were fighting the latest versions of M4 Sherman.

A specification was issued in mid-1942 for a Semovente that could support the infantry, but also fight against such modern threats using the heavy Italian Cannone da 105/23. At that time, Odero-Terni-Orlando (OTO) and the consortium Ansaldo-FIAT, two Italian tank manufacturers, proposed two different self-propelled gun prototypes. The OTO proposal was to mount the 105/23 cannon on the hull of the heavy tank P26/40, which was still under development and entered into service only after September 1943.

However, FIAT-Ansaldo could build a prototype of their vehicle faster because the project was based on the already under construction M15/42 Italian medium tank hull. This had already been tested in February-March 1943 and under construction since April of that same year.

At the same time, the FIAT-Ansaldo project was also chosen because the manufacturers had mastery over the components involved. It also required only small modifications to the assembly lines. This meant it could be put into production very quickly. The Italian Army evaluated it positively for two simple reasons. Firstly, because there were already existing courses for the training of new crews (and mechanics) of self-propelled guns on almost identical chassis. Secondly, because a self-propelled gun based on the modified M15/42 chassis was lighter than a self-propelled gun on the P26/40 hull, which meant that the FIAT-Ansaldo self-propelled gun needed a less powerful gasoline engine. This was a big advantage for the Italian Army that had to replace diesel engines with gasoline engines after 1942 due to the limited resources available.

Prototype history

A prototype was built between 16th and 28th January 1943 and was armed with a prototype of the 105/23 Mod.1943 cannon. It was first examined by the Ispettorato delle Truppe Motorizzate e Corazzate (Eng. Inspectorate of Motorised and Armored Troops) and the Ispettorato dell’Arma d’Artiglieria (Eng. Inspectorate of the Artillery Corps) on 1st February. It was presented to the Centro Studi della Motorizzazione (Eng: Centre for Motorisation Studies) in Rome on 27th February for official testing. Early photos of the prototype show that the vehicle initially lacked a radio antenna, racks for the 20-liters cans, and headlights, which were fitted before the presentation in Rome. In particular, 6 racks were mounted on the prototype, two on the front, two on fenders, and two more on the rear of the vehicle.

The testing of the prototype took about a month. In the end, the Regio Esercito was very impressed by the firepower of the 105 mm cannon. On 29th March 1943, the High Command of the Regio Esercito ordered 130 vehicles divided into two batches, the first batch of 30 and a second of 100 self-propelled guns. It was now officially renamed as the ‘Semovente FIAT-Ansaldo su scafo M43 da 105/25’, abbreviated to ‘Semovente M43 da 105/25’ (Eng: Self-propelled gun FIAT-Ansaldo on hull M43 armed with a 105/25). It was nicknamed “Bassotto” (Eng: Dachshund) by the crews for its lower and larger profile.

Orders

In addition to the first order of 130 units placed in March 1943, the FIAT and Ansaldo consortium received new contracts from the Regio Esercito for the production of 105 mm-armed self-propelled guns. On 10th May 1943, the total order was increased to 200 vehicles, and then to 454 in June. Some sources mention 494 units ordered in July 1943, but this can not be confirmed due to the partial loss of the Ansaldo Archives following the armistice of September 1943.

The first vehicles produced in the gigantic Ansaldo-Fossati plant in Sestri Ponente, near Genoa, Northern Italy, were completed at the end of May 1943. They were delivered to the Regio Esercito at the beginning of July. According to the records, by 30th June, a total of 30 M43 105/25s had already been completed. After the Armistice of Cassibile and the occupation of the central and northern parts of Italy by the Wehrmacht, production was initially interrupted. However, the Generalinspekteur der Panzertruppen (Eng. Inspector General of the Armed Forces) quickly evaluated the self-propelled gun, and, judging it positively, production was restarted.

By the end of 1943, the Ansaldo-Fossati plant in Genoa had produced another 24 M43 self-propelled 105/25 vehicles for the Germans. However, in 1944, only 67 more were produced due to bombing, lack of raw materials and strikes. The production was not continued in 1945 because of heavy Allied bombing that stopped the production of most of the plant and because the Generalinspekteur der Panzertruppen, together with the Reichsministerium für Rüstung und Kriegsproduktion (Eng: Reich Ministry for Armaments and War Production) in Berlin, had decided to discontinue production of all Italian vehicles except the Panzerspähwagen AB43 203(i), Panzerspähwagen Lince 202(i) and the Sturmgeschütz M43 mit 75/46 852(i) self-propelled vehicle which they considered adequate.

The total production of the Semovente М43 da 105/25 was 121 units between April 1943 and December 1944.

Design of the “Bassotto”

Hull and armor

The M42 hull was 14 cm longer than the previous M40 and M41 hulls. The new M43 hull (also called M42 ‘Lungo’ – Eng. ‘Long’) was even longer, with 4 cm more than the M42, reaching a length of 5.10 m (18 cm more than the M41), 17 cm wider (2.40 m compared to 2.23 m of the M42) and 10 cm lower (1.75 m compared to 1.85 m of the M42). Finally, the flameproof armor plate separating the engine compartment from the fighting compartment was moved back 20 cm, increasing the space for the crew. All these modifications brought the total weight of the vehicle to 15.8 tonnes battle-ready compared to the 15 tonnes of the M42.

This made the vehicle’s silhouette more elusive and also allowed the cannon to be positioned in the center of the superstructure, instead of being moved to the right, like on the previous chassis.

The armor was both bolted to an internal frame and partially welded (a great innovation for Italian vehicles) and had great thickness compared to Italian standards. The hull armor was 50 mm on top and 25 mm on the bottom. The superstructure had an armor plate 75 mm thick (some sources mention 70 mm) frontally, 45 mm on the sides, while the rear was protected by a plate 35 mm thick. A plate of the same thickness protected the back of the engine compartment.

The roof and floor of the vehicle were 15 mm thick. New to the vehicle were the side skirts that were divided into three parts. These were presumably 5 mm thick. They partially protected the sides of the vehicle. The side skirts had a hole in the back to allow the crew to be able to reach the track tension adjuster.

In general, the protection was increased compared to the 50 mm frontal, 35 mm side, and 20 mm on the rest of the frame of the previous M42, or the 50 mm frontal, 25 mm lateral, and 15 mm rear of the M41, even if the Italian industry was not able to provide ballistic steel of good quality. In fact, the Italian armor was fragile compared to the armor of equal thickness of other nations involved in the war. When an enemy round hit Italian armor, the armor often broke or splintered even without being penetrated, causing damage to the vehicle and/or crewmembers and leading to the need to send the vehicle to specialized workshops to replace the damaged armor plates.

Exterior Features

On the roof, on the left side, there was the radio antenna, a fully rotatable periscope and an opening for the cannon. The commander was equipped with an optical sighting system produced by Ansaldo and weighing about 13 kg. On the left front mudguard, there was a support for the jack. On the sides of the superstructure, there were two headlights for night operations. The engine deck had two large inspection hatches equipped with grills for engine cooling. Behind them were the fuel tank cap and two grills for radiator cooling. At the rear, there was a spare wheel, a hole for the engine crank, the towing hook and a smoke grenade launcher system consisting of a launcher and a rack carrying smoke grenades to reload the launcher.

On either side of the engine deck, on the rear fenders, there were two storage boxes and the mufflers covered by a steel shield to protect them from impacts. Six racks for 20-liter cans were placed on the sides of the vehicle, three on each side, just like other Italian self-propelled guns and tanks. In fact, from 1942 onward, the racks were factory fitted on all vehicles, as most would have gone to operate in Africa, where the cans would have increased the range of the vehicle. It should be noted, however, that in the majority of cases, on the Semoventi M43 da 105/25, the cans were not transported because, in Italy, it was not that difficult to find fuel.

Suspension

The suspension was a semi-elliptical leaf spring type. On each side, there were four bogies with eight doubled rubber road wheels paired on two suspension units in total. This suspension type was obsolete and did not allow the vehicle to reach a high top speed. In addition, it was very vulnerable to enemy fire and mines.

The tank had 26 cm wide tracks, with 86 track links per side. The drive sprockets were at the front and the idlers and track tension adjusting mechanism were at the back, with three rubber return rollers on each side. The small surface area of the tracks (20,800 cm²) caused a ground pressure of 0,76 kg/cm² (to give an example, the Soviet SU-100 had 0,56 kg/cm² and the German StuH 42 0,92 kg/cm²), increasing the risk that the vehicle would bog down in mud, snow or sand.

Main armament

The main armament was a Cannone da 105/25 (sometimes also called Mod. S.F. ‘Serico’ for Spherical) produced by Ansaldo. It was developed on the basis of the Obice da 105/23 Mod. 1942, a howitzer developed by OTO-Melara as a prototype for divisional artillery together with the Obice da 105/40 Mod. 1938.

Unfortunately, the two prototypes were produced and tested by the Regio Esercito too late. 600 of the Mod. 1938 were ordered, but only a few were delivered before the Armistice of Cassibile. The Mod. 1942 was not ordered in time.

At least two prototypes of the Obice da 105/23 Mod. 1942 were produced. One, or perhaps more, were on a fielded carriage and one was on a spherical support meant for the prototype of the Semovente M43 da 105/25.

The field version of the gun had a maximum range of 13 km and a practical range of 2,000-2,500 m for anti-tank ammunition. It had a practical firing rate of 8 rounds per minute. Obviously, inside the narrow fighting compartment of the self-propelled gun, this dropped dramatically.

The gun weight is not given in the sources, but we can assume that it did not exceed one tonne together with its spherical support. The Cannone da 105/28 Mod. 1912, also produced by Ansaldo (and with which it shared the ammunition) had a barrel length of 2.987 m (compared to 2.6 m of the 105/25) and weighed 850 kg.

Thanks to the enlargement of the vehicle, the cannon’s spherical mount was centrally placed on the front plate. The gun had a horizontal traverse of 18° to the right and 18° to the left, as well as an elevation of +18° and a depression of -10°.

After the war, some 105/25 guns were used as anti-tank artillery in the bunkers of the fortification line called the “Alpine Wall”, on the border with Yugoslavia, in the early years of the Cold War.
No other data is available on this artillery piece due to the few units produced and their limited use.

Secondary Armament

The secondary armament consisted of a Breda Mod. 38 medium machine gun, a vehicle version of the Breda Mod. 37 medium machine gun used by the Italian infantry. The machine gun weighed 15.4 kg and was chambered with the 8×59 RB Breda cartridge. It was specially developed for Italian machine guns in 1935 and had a muzzle velocity of 775 m/s. The Breda Mod. 38 had a theoretical firing rate of 600 rounds per minute, which in practice dropped to about 350 rounds per minute. One of the advantages of this machine gun, in addition to its reliability, was its small size. In fact, the machine gun was only 89 cm long, taking up little space when stowed inside the vehicle.

Some sources claim that, due to the lack of Breda machine guns or for simple convenience, some German crews who received these self-propelled guns replaced the Breda Mod. 38 with German-made machine guns, such as the MG34 or MG42. This would have greatly increased the anti-aircraft firepower of the vehicle, but there is no photographic evidence or data confirming the use of Mauser machine guns on the self-propelled vehicles.

Although lacking interior space, the crew brought onboard the Semovente M43 their Carcano Mod. 91 rifles, MAB 38 submachine guns and OTO, Breda or SRCM Mod. 35 hand grenades or their German counterparts for close defense against enemy infantry.

Ammunition

The 105/25 Cannon could fire a wide range of projectiles:

Name	Type	Weight (kg)	Explosive Filler (kg)	Maximum Range (m)	Penetration at 1,000 m
Cartoccio Granata da 105 Mod. 32	HE	16.3	2.35 TNT	13,640
Cartoccio Granata da 105 Mod. 36	HE	16.125	1.76 TNT	13,640	//
Proietto Perforante da 105	APC-T	15.65	0.3 TNT	12,500	72 mm at 90°
Proietto Controcarri Effetto Pronto	HEAT	14	//	12,630<>	//
Proietto Controcarri Effetto Pronto Speciale M43	HEAT	14	2.35 TNT	9,400, effective 2,000-2,500	120 mm at 90°

The Cartoccio Granata da 105 Mod. 32 and the Cartoccio Granata da 105 Mod. 36 were almost identical, but the Mod. 36 with ADE M32 or ADE M36 nose percussion fuze could detonate the ammunition on impact or in the air.

Information about the anti-tank ammunition is provided only by some accounts. The muzzle velocity of the Armor-Piercing, Capped – Tracer (APC-T) was 500 m/s and it could pierce a maximum of 90 mm of ballistic steel inclined at 90° at 100 meters, 80 mm at 500 meters and about 60 mm at 2,000 meters.

The penetration and muzzle velocity of the Proietto Controcarri Effetto Pronto High-Explosive Anti-Tank (HEAT) rounds are unknown. The Proietto Controcarri Effetto Pronto Speciale M43 had a muzzle velocity of 510 m/s. It could pierce a 120 mm plate inclined at 90°. The maximum range was of 9,400 m with anti-tank effectiveness at a maximum distance of 2,000-2,500 m.

There were also smoke and incendiary projectiles developed for the field artillery version. These were apparently almost never used on the Semovente.

The Breda Mod. 38 machine gun was fed by top curved magazines with 24 bullets. This was not ideal, because it did not allow for continuous fire against aircraft or infantry.

The standard 8 mm ammunition had a muzzle velocity of 780 m/s and could penetrate a 11 mm RHA (Rolled Homogeneous Armor) plate at 90° at a distance of 100 m.

Although hardly ever used on self-propelled guns, the machine gun could also fire M.39 AP (Armor Piercing) shells. The bullet weighed 12 grams and could penetrate an armor plate of 16 mm at 100 m.

In the wooden rack on the right of the vehicle, there were 864 shells, equivalent to 36 magazines.

Interior Features

Starting from the front of the vehicle, there was the transmission connected to the braking system, which had two armored inspection hatches. These could be opened from the outside by means of two handles, or from the inside by means of a knob located on the right side of the vehicle, which could be used by the gunner.

On the left was the driver’s position with the seat with a fold-down back for easy access. In front, it had the two steering tillers, an armored slot that could be closed with a lever and a hyposcope for driving with the slot closed. On the left was the control panel and, on the right, the gun breech.

Behind the driver, there was a box rack for twelve 105 mm rounds arranged in rows of 4 rounds, with a padding on top that also served as a seat for the loader. Behind this, there was a rack of 24 105 mm rounds, also arranged in rows of 4 rounds.

The loader had, on the left, the radio system and, above him, one of the two armored hatches. In case of an air attack, the loader would also have to use the anti-aircraft machine gun.
On the right side of the fighting compartment, there was the gunner’s/commander’s seat without a backrest. In front of his seat, the gunner had the elevation and swing handwheels. On the left was the gun breech. Interestingly, the lever for opening the breech was placed on the right side of the breech. This meant that, after firing, the gunner had to rotate his torso by about 90° (a very uncomfortable action in the narrow space) and open the breech.

On his right was the support for the anti-aircraft gun (when not in use), a maintenance kit and a fire extinguisher. Behind the support was a wooden rack for the ammunition of the machine gun. In order to prevent the magazines from falling on rough terrain, the rack had a closable curtain.

Behind the gunner/commander was the last ammunition rack with 12 105 mm rounds arranged in three rows of 4 rounds.

On the rear wall of the fighting compartment, there were four cumbersome filters for air, oil and two for the fuel. The engine fan, an engine cooling water tank, the batteries for engine ignition were also there, and the transmission shaft ran through the entire fighting compartment, dividing it in half.

Crew

The Semovente M43 da 105/25 was the only self-propelled gun of World War II armed with a 105 mm gun, but with only 3 crew members. The driver was positioned on the left of the vehicle. On his right was the gun breech. The commander/gunner was positioned on the right of the vehicle and loader/radio operator on the left, behind the driver.

Some sources state that the Germans preferred to add a fourth crewman behind the gunner, who would load the gun. The loader’s seat would be occupied by the commander/radio operator and the gunner would perform only one function. Obviously, adding a fourth crewman meant reducing the quantity of 105 mm ammunition on board and, above all, operating in a fighting compartment that was already cramped with three men.

Engine

The engine of the Semovente M43 da 105/25 was inherited from the previous self-propelled guns on the M42 chassis, which in turn inherited it from the M15/42. This was the FIAT-SPA T15B. ‘B’ stood for ‘Benzina’ (Eng. Petrol). This was a petrol water-cooled 11,980 cm³ engine developing 190 hp at 2400 rpm. It was developed by FIAT and one of its subsidiary companies, the Società Piemontese Automobili or SPA (Eng. Piedmontese Automobile Company). Previously, on Italian vehicles such as the M11/39, M13/40 and M14/41 and the self-propelled guns on their chassis (M40 and M41), the engine was a diesel. Due to the scarcity of fuel as early as the beginning of 1942, the Royal Italian Army converted to gasoline with the M15/42. However, due to the size of the 307 liter gasoline tank (compared to 145 liters-tanks of the previous diesel engined tanks) and the fire extinguishing system, the chassis was lengthened by 14 cm (5.06 m compared to 4.92 m of previous models).

The engine was quite reliable, with a power-to-weight ratio of 12 hp/tonne and was connected to the FIAT 8 F2 transmission (the same as on the previous vehicles) with four forward gears and one reverse gear. This guaranteed a maximum speed of 35 km/h and a range of 180 km.

Radio equipment

The radio onboard the Semovente was the standard Italian tank equipment, the Magneti Marelli RF1CA produced in Sesto San Giovanni, near Milan. It had a weight of 13 kg. The transceiver had the possibility of adjusting the sensitivity of the amplifier by a two-position switch, ‘Vicino’ (Eng: near) for distances not exceeding 5 km and ‘Lontano’ (Eng: far) for distances between 5 and 12 km, the maximum range of the radio.

The equipment was placed on the left side of the hull, above the fender, under its standard 1.8 m high antenna that could be lowered 90° to the rear by means of a knob. The 8 watt radio transformer and four Magneti Marelli 3NF-12-1-24 batteries were on the radio’s right. Further to the right was the driver’s instrument panel.

Service History

Regio Esercito

The first Semoventi M43 da 105/25 were completed at the beginning of May 1943. The first self-propelled gun, plate number ‘R.E. 5846’, was delivered on 2nd July 1943, after testing at the tank crew School of the Royal Army in Nettunia, about fifty kilometers from Rome.

It was foreseen by the Regio Esercito that these vehicles would be used in Gruppi Corazzati (ENG. Armored Groups) of 12 self-propelled guns, subdivided into 3 platoons of 4 vehicles. These would have the task of supporting the actions of the P26/40, then at the beginning of production, and of the P30/43, which was still under development.

Five Armored Groups were created by the Regio Esercito, the DC° Gruppo Corazzato, DCI° Gruppo Corazzato, DCII° Gruppo Corazzato, DCIV° Gruppo Corazzato and DCV° Gruppo Corazzato.

On 25th July 1943, Mussolini was arrested by order of the King of Italy, Vittorio Emanuele III d’Italia, and the Gran Consiglio del Fascismo (Eng: Grand Council of Fascism). The new government, presided over by Prime Minister Pietro Badoglio, ordered the Army to continue to fight alongside the Axis powers even if, almost immediately, in secret, it tried to negotiate an armistice with the Allies.

This situation brought much confusion to the soldiers who, in many cases, were not even informed about what had really happened in Rome.

Only the DCI° Gruppo Corazzato and the DCII° Gruppo Corazzato stationed at Nettunia for crew training received all 12 vehicles.

From what is reported, the DCI° Gruppo Corazzato, assigned to the 135ª Divisione Corazzata ‘Ariete II’ (Eng. 135th Armored Division), was the only one to participate in military actions of the Regio Esercito, participating in the Defense of Rome on 9th September 1943.

As mentioned, Italian Prime Minister Badoglio tried to sign an armistice with the Allied powers and succeeded in his intent only on 3rd September 1943.

The official proclamation was made by U.S. General Dwight Eisenhower on Radio Algiers at 6.30 p.m. and then repeated by Pietro Badoglio in Italian on Radio EIAR at 7.42 p.m. on 8th September 1943.

Needless to say, this threw almost all units of the Royal Army into chaos, as they did not receive precise orders and were forced to act on their own initiative.

Immediately after the Armistice, the German command, which had foreseen the Italian defection, launched Fall Achse (Eng. Operation Axis), meant to take apart the Italian Royal Army.

On 9th September 1943, the morning after the radio announcement of the Armistice, the 135th Armored Division engaged German troops in the city of Cesano, and on the Via Ostiense leading to Rome.

It is not clear in which part of Rome they took part in the fighting, as the Armored Division fought in every neighborhood of Rome supporting the 21ª Divisione fanteria “Granatieri di Sardegna” (Eng. 21st Infantry Division) at Porta San Paolo, the members of the Polizia dell’Africa Italiana (Eng. Italian Police of Africa) and the 18° Reggimento Bersaglieri (Eng. 18th Bersaglieri Regiment) near the Colosseum.

During the fighting, four Semoventi M43 da 105/25 of the DCI° Gruppo Corazzato were destroyed. It is not clear whether they were all destroyed by German weapons or whether some were sabotaged by the crews before escaping and joining the Italian partisan resistance or returning to their homes.

Wehrmacht

Immediately after the Armistice, the Germans launched Fall Achse, which lasted until 19th September 1943 and resulted in the deaths of between 20,000 and 30,000 Italian soldiers, the capture of just over one million Italian soldiers, 2,700 anti-tank or anti-aircraft guns, 5,500 howitzers or field guns, 16,600 trucks or cars and 977 armored vehicles.

Among the 977 captured armored vehicles were the 26 surviving Semoventi M43 da 105/25, which were later renamed Beutepanzer Sturmgeschütz M43 mit 105/25 853(i) (Eng. Captured Assault Gun with 105/25 gun Italian).

For the duration of the war, the Germans received another 91 StuG M43 mit 105/25 853(i) produced after the Armistice. This means that the Wehrmacht used a total of 116 M43 mit 105/25.

While the Germans operated relatively large numbers of M-series tanks and some older Semovente in the Balkans for anti-partisan operations, the more modern Semovente M43 da 105/25 were only used in Italy. By the end of September 1943, the German units had around 221 (both 75 and 105 mm) Semovente at their disposal.

At the end of 1943, the 26th Panzer Division had 7, the 356th Infantry Division had 20 and the Panzer training unit Sued had two Semovente M43 da 105/25 vehicles. The greatest concentration of these vehicles was allocated to the SturmGeschütz Brigade 914 (Assault Gun Brigade) and SturmGeschütz Brigade 21. By February 1944, the 914th Brigade had some 31 Semovente da 105/25 in its inventory. The 21st Brigade continued to operate the Semovente da 105/25 up to the war’s end. By mid-March 1945, it had 56 such vehicles, three of which were given to this unit by the 356th Infantry Division.

The M43 da 105/25 was used by the German mainly in anti-tank roles when possible. The Italian vehicles, in general, were plagued by the lack of spare parts and ammunition. So the relatively large number of vehicles did not always necessarily mean that all were operational, as most would be often stored at the rear for much needed repairs. One occasion where the M43 da 105/25 was used was by Panzer Regiment 26 which attacked the Allied positions at Mozzagrogna with the 65. Infantrie-Division at the end of November 1943. The attack was spearheaded by 6 Semovente (three 105 and three 75 mm) and five Flammenpanzer III flame tanks. One flame tank was destroyed by PIAT attacks of the 1st/5th Royal Gurkha Rifles or the 1st Royal Fusiliers when he tried to attack the allied HQ at the church in Mozzagrogna with his Flammenpanzer III.

The unit was later on attacked by Allied ground attack planes and decimated, with only one Semovente M43 da 105/25 managing to survive. The Germans were generally satisfied with the Semovente vehicles, but noted that these lacked proper observation sights, had insufficient frontal armor and a cramped crew compartment.

When production resumed, the Germans ordered the vehicles to be modified by adding four large teeth to the sprocket wheel, which decreased the risk of the tracks falling off or coming loose. Some sources also mention that the Germans had replaced the Italian radio system with a German one and also the machine guns, but there is no evidence of these changes.

Esercito Nazionale Repubblicano

After 8th September 1943, the Germans freed Benito Mussolini and took him to Germany to discuss the continuation of the war alongside the Axis with Adolf Hitler. On 23rd September, he returned to Italy as ‘Duce’ and founded the Repubblica Sociale Italiana or RSI (Eng. Italian Social Republic), a collaborationist state in the territories not yet occupied by the Allies. Some Italian prisoners who had remained loyal to Mussolini immediately joined the new Esercito Nazionale Repubblicano, ENR (Eng. National Republican Army).

This new army was armed with few armored vehicles, artillery pieces and any other type of military equipment because, after the armistice, the German soldiers no longer trusted their Italian allies.
A good part of the units of the new army and of the Guardia Nazionale Repubblicana, or GNR (Eng. Republican National Guard), had to arm themselves as best they could. They produced several homemade vehicles or recovered abandoned vehicles in very bad condition from former Regio Esercito depots.

One of these units was the Gruppo Corazzato ‘Leoncello’ (Eng. Armored Group) which, during the last two years of the war, was equipped with only 7 L3/35 light tanks, 1 L6/40 light tank, 5 tanks of the ‘M’ series (4 M13/40 and 1 M15/42) and a Semovente M43 da 105/25, the latter from February 1945.

It is not clear how the unit took possession of the self-propelled gun. It is supposed that it was one of the examples in service since February 1944 with the 1° Deposito Carristi (Eng: 1st Tanker Depot) in Verona, where it would have been used for the training of tankers. According to the Army Staff, this vehicle had damaged optics.

The vehicle, part of the Squadrone Comando (Eng. Command Squadron), received the nickname ‘Terremoto’ (Eng. Earthquake) painted in capital letters on the front plate. It also had an Italian tricolor and, on the sides, a lion holding between the paws the fascio littorio, symbol of the Partito Fascista Italiano (Eng: Italian Fascist Party) and Italian flags.

From January to the first days of April, the vehicle was not used in anti-partisan actions, but only for training and was stationed in Polpenazze sul Garda, 130 km east of Milan, at the headquarters of the Armored Group. In April 1945, when the situation was desperate, the Command Squadron was stationed in Milan, avoiding the popular strike and insurrection, but without the Semovente. On the night of 24th April 1945, the day of the partisan insurrection that, in a few days, would lead to the complete loss of the main cities of Northern Italy, such as Turin, Genoa and Milan, a unit formed of the five ‘M’ series tanks, some light tanks and the Semovente, under the orders of the Armored Group Commander Gianluca Zuccaro, moved towards Milan.

During the night, an Allied aircraft noticed the column and attacked the unit repeatedly, but only with machine guns. It disabled an ‘M’ tank that was abandoned on the roadside the morning of 25th April.

After receiving orders to surrender from the Armored Group Headquarters, the tank crews sabotaged the vehicles near Cernusco sul Naviglio, 100 km from Polpenazze and surrendered to the partisans.

Variants

Semovente M43 da 75/34

This was a self-propelled gun built on the same hull, but with the Cannone da 75/34 cannon Mod. S.F., the same as on the Semoventi M42M da 75/34. Only 29 were built and they were only used by the Germans in tank destroyer Regiments in Italy and the Balkans. It had more internal space due to the smaller dimensions of the 75 mm cannon breech. The total number of rounds transported was 45, giving the crew more space.

Semovente M43 da 75/46

Developed in 1943, with heavy armament and armor, the main armament was a powerful Cannone da 75/46 C.A. Mod. 1934 and the welded armor had a maximum thickness of 100 mm on the frontal plate, the only Italian vehicle with this thickness. Eleven were built during 1944-1945 and only used by the German Army in one tank destroyer Regiment in the defence of the Gothic Line. One was captured by Brazilian soldiers in Piacenza and one was captured by partisans in Milan. None survived the war.

Conclusion

The Semovente M43 da 105/25 was produced in small numbers during the war and could make little contribution to the Axis forces during the war. Most were used by the Germans, but the lack of supplies and ammunition hindered their use. Their gun proved to be an excellent anti-tank artillery piece. Unfortunately, no M43 has survived to the present day.

Semovente M43 da 105/25 Specifications
Dimensions (L-W-H)	5.10 x 2.40 x 1.75 m
Total weight, battle ready	15.8 t
Crew	3 (commander/gunner, driver, loader/radio operator)
Propulsion	FIAT-SPA 15TB petrol engine with 307 l tanks, 192 hp
Range	180 km
Maximum speed	35 km/h on road; 10/12 km/h on various terrain
Main Armament	Cannone da 105/25 with 48 rounds
Secondary armament	Breda 38 8 mm machine gun with 864 rounds
Armor	75 mm front, 45 mm sides, 35 mm rear and 15 mm roof and floor
Total production	121 Semoventi used by the Regio Esercito (30), the Wehrmacht (112) and the ENR (1)

Sources

Gli autoveicoli da combattimento dell’Esercito Italiano (1940-1945) – Nicola Pignato and Filippo Cappellano
I mezzi blindo-corazzati italiani 1923-1943 – Nicola Pignato
I reparti corazzati della Repubblica Sociale Italiana 1943/1945 –
I mezzi corazzati Italiani della Guerra Civile 1943-1945 – Paolo Crippa
T. J. Jentz and W. Regenberg (2008) Panzer Tracts No.19-1 Beute-Panzerkampfwagen
F. Cappellano and P.P. Battistelli (2012) Italian Medium Tanks 1939-45, Osprey Publishing