The Semovente series of assault guns were probably the best WWII Italian AFVs built in any significant numbers. The first were built in 1941, simply being M13/40 tanks (p.W:GL32) with the turret replaced by an armored box housing a 75mm howitzer in a ball mount. Although the new cannon had limited effectiveness against tanks, it had a much more useful HE shell than the 47mm gun of the M13/40. When a new Italian tank entered production, the Semovente switched to the new chassis, so versions were also built on the M14/41 and M15/42 hulls. The vehicle was also smaller and lighter than the later German Hetzer.
Production numbers are somewhat hazy. At least 60 were built on the M13/40 hull, 120 on the M14/41 hull and 20 on the M15/42 hull before Italy surrendered. Over 200 more of various types (mostly with a longer 75mm gun or a 105mm howitzer) were produced for German use. Once source lists 780 of all versions built, but this is rather higher than the detailed numbers indicate.
The Semovente M 40 has a crew of three. The driver sits in the body. The commander loads the howitzer and, if required, operates the 8mm Breda. The gunner fires the 75/18 Model 34. It uses 4.2 gallons per hour at routine usage.
Subassemblies: Small Tank chassis +3, Large Weapon superstructure
[Body:T] +1, tracks +2.
Powertrain: 93-kW diesel engine w/93-kW tracked drive train
and 48 gallons fuel in standard fuel tank [body]; 8,000-kWs batteries.
Occupancy: 1 CS Body, 2 CS both Cargo: 2.5 Superstructure,
3.8 Body.
| Armor | F | R/L | B | T | U |
| Body | 4/115 | 4/100 | 4/100 | 4/55 | 4/25 |
| Tracks | 4/35 | 4/35 | 4/35 | 4/35 | 4/35 |
| Superstructure | 4/195 | 4/95 | 4/95 | 4/35 | 0/0 |
Weaponry
75mm Short Tank Gun/M34 [Super:F] (44).
Ground LMG/8mm M38 Breda [OM:F] (1,104).
Statistics
| Size: 17'x7'x6' | Payload: 0.83 tons | Lwt: 13 tons |
| Volume: 58 | Maint.: 59 hours | Price: $11,600 |
HT: 10.
HP: 1,000 Body, 120 Superstructure, 400 each Track.
| gSpeed: 20 | gAccel: 2 | gDecel: 20 | gMR: 0.25 | aSR: 4 |
Design Notes
The design purchased 1,000 rounds of LMG ammo and 48 rounds of TG ammo.
The 8mm Breda LMG was usually stowed inside the vehicle. Later models used the 6.5mm M30 Breda.
Variants
In 1943, plans were made to install a longer gun (75mm Medium TG),
with the vehicles mounting the shorter gun transferred to support infantry.
Only 90 with the longer gun were built, most used by the Germans.
The M42L da 105/25 (1943) had a 105L25 howitzer (105mm Short Howitzer). Only about 30 were built before the Italian surrender, with about 61 later built for the Germans. Some (11) that found their way into German service replaced the howitzer with a 75mmL46 gun (75mm Long TG).
The Germans designated Semovente M 40 da 75/18 vehicles they impressed into service as the StuG M40(i).