SPG – 90 built
A specification was emitted in mid-1942 for an SPG that could support infantry, but also double as tank hunter, using the heavy 25 caliber Cannone da 105 mm (4.13 in). At that time, Odero-Terni-Orlando (OTO) and Ansaldo proposed prototypes. OTO’s proposition was to fit the 105/23 gun on a P26/40 heavy tank chassis. However, the prototype built at Ansaldo, based on the M15/43, and presented at the Study Center of Motor Vehicles, on 28 February 1943, was eventually tested and approved by the Comando Supremo, for a production run of 878 vehicles. It entered production on 2 April 1943, and was in service between June and September, before the Italian Armistice, under the designation Semovente da 105/25 su scafo M43.
Design of the “Bassotto”
This heavy SPG followed the path of other Semovente in service. It was, however, based on the latest chassis available, the lengthened Carro Armato M15/42 medium tank, in its 1943 version. For the task, the chassis was slightly widened, reaching 7.9 feet (2.4 m) instead of 7.3 feet (2.20 m). The gun itself was positioned on the centreline, with a casemate protected by a 75 mm (2.95 in) frontal sloped plate, 50 mm (1.97 in) of armor on the sides and only 15 mm (0.59 in) on the roof and bottom. The driver was located on the left hand side and had a hinged armored shutter with a sight slit. A small headlight was fitted left of him, on the sloped side. A Magneti Marelli RF1 CA emitter/receiver was also fitted, with its whip antenna located on the left side of the roof. Two large roof hatches were installed, for easier access. There was a mount-point for a Breda 8 mm (0.31 in) machine-gun on an AA pintle mount and a hull-mounted Breda 8 mm (0.31 in) with 864 rounds as secondary armament. The main gun was derived from the 1916 105/28 field gun and had a rather low muzzle velocity, around 650 m/sec (2130 ft/s) with AP rounds. It had a 34° traverse and -12°/+ 22° depression/elevation. But it could be deadly effective at short range, because of its heavy HE shells. At 15.9 tons and a 192 hp engine, it was capable of a top road speed of 35 km/h (22 mph). The crew of three comprised the driver, the commander, that doubled as gunner, and the loader, that doubled as radio operator. The Semovente da 75/46 tank hunter was also built on the same chassis, and it was the first Italian vehicle with a welded construction.
Production and service
The armistice came after only 30 of these vehicles were built. The days following the armistice, these Italian SPGs saw action with the 135ª Armored Division “Ariete II”, against German troops near Rome. However, the factory and all vehicles were later taken over by German forces, and the Semovente 105/25 was renamed Sturmgeschütz M43 mit 105/25 853(i). The production line was reactivated and 60 more of these were delivered until 1944, for the German forces. Most were used for the defense of the Gothic line and some were passed on to the Italian forces of the puppet republic of Salo, and stayed in service until May 1945 in northern Italy. The Semovente 105/25 was nicknamed “Bassotto”, and the crews generally liked it. It was the most heavily armed SPG in Italian service, presented a low silhouette, and was well protected and reliable. Surviving German vehicles ended stripped of their main guns, which were recycled into the Alpine Valley bunkers.
Links about the Semovente da 105/25
Semovente M43 da 105/25 specifications
|Dimensions (L-W-H)||5.1 x 2.40 x 1.75 m (19.8 x 9.3 x 5.9 ft)|
|Total weight, battle ready||15.8 tons|
|Crew||3 (commander/gunner, driver, loader/radioman)|
|Propulsion||SPA 15TB M-15 diesel (360 l), 192 hp (143.17 kW), 15 hp/t|
|Suspension||Vertical volute springs|
|Maximum speed (road)||38 km/h (24 mph)|
|Operational range||150 km (93 mi)|
|Armament||Main: 105 mm (2.95 in) L28 34, 48 rounds
Secondary: 8 mm (0.31 in) Breda 38 machine gun, 1100 rounds
|Armor||From 30 to 100 mm (1.18-3.94 in)|