In July 1927, at the initiative of General Armando Armani, Chief of Staff of the Italian Royal Air Force, a meeting was held by the leadership of the Superior Technical Committee for Weapons and Ammunition (CSTAM). The agenda was to discuss aviation armament exceeding 8 mm caliber.
It must be said that, by 1927, this was a truly revolutionary event. Aircraft speeds and strength had not yet reached the level where rifle-caliber machine guns became ineffective against them. In no other country in the world had developers even considered heavy machine guns.
General Armani’s proposal was met with keen interest from the Navy’s representative, Admiral Foschini, and the Army’s representative, General Cortese, who were present at the meeting.
The final decision of the meeting was an order from the three branches of service for a universal large-caliber weapon, equally suitable for anti-aircraft, anti-tank, and aviation use. A caliber around 12 mm was deemed sufficient, although it was not clearly specified in the technical requirements. The primary heavy automatic weapon in service with the Italian army and navy was the old 2-pounder Vickers from World War I, and apparently, the military leaders themselves still had a vague idea of the required characteristics for the future weapon, given the diverse demands of the different services.
Early Prototypes and Trials
Therefore, the competitive trials of the samples received by the end of 1929 comprised a very heterogeneous collection. The latest weapon samples from around the world were displayed at the La Spezia firing range. The most powerful was John Browning’s 37mm Colt anti-aircraft gun. In the lighter weight category were a prototype of the newest French 13.2mm Hotchkiss machine gun, the British 12.7mm Vickers HV, as well as domestic products—the Fiat-SAFAT and Breda heavy machine guns, which deserve a more detailed look.
Very little is known about these Italian armament samples, and information is often quite contradictory. Nevertheless, some details can be pieced together.
The Fiat heavy machine gun, designed by the Italian engineer Giuseppe Mascuracci, conceptually replicated the 6.5 mm version of the 1926 model, a short-recoil weapon, but considerably scaled up in size. The first versions of this weapon, primarily intended for naval use, appeared even before the aforementioned CSTAM meeting in 1926. The purpose of this weapon was quite non-trivial: the idea behind creating a heavy machine gun was the need for a rapid-fire weapon on large ships to shoot down enemy torpedoes!
Regarding the caliber of this weapon, there are discrepancies. While the encyclopedia “Breda Meccanica Bresciana” by Andrea Curami, Paolo Ferrari, and Achille Raztelli states the Fiat machine gun caliber was 12.0 mm, George Chinn believes it was 12.7 mm, and several other sources offer a 12.5 mm caliber version. Most likely, according to Italian sources, which seem more reliable, the Fiat machine gun’s caliber was indeed 12.0 mm, although the cartridge type remains unknown.
The 1926 model Fiat machine gun was quite bulky, almost 2 meters long and weighing 41 kg. When mounted on a pedestal for naval use, the machine gun was equipped with a water-cooling jacket, increasing its mass to 218 kg. The army version with air-cooled barrel was slightly lighter at 190 kg. Feeding was from box magazines, similar to the 6.5-mm model, inserted from the right side of the receiver. Magazine capacity varied by source, stated as 10, 20, 25, and 30 rounds. The machine gun’s rate of fire was 300 rounds per minute. A 1.2 m movable barrel provided a 40-gram bullet with an initial velocity of 940 m/s. The machine gun was equipped with a pistol grip with a trigger. The rigidity of the system was ensured by a massive mount with flywheels for vertical and horizontal aiming.
In the 1928 version, the external framework was somewhat reworked, mainly to lighten the design. The weapon’s length was slightly reduced. Instead of a pistol grip, “Maxim-style” handles with a trigger and a folding stock appeared. The wheeled army mount was also redesigned. Inconvenient aiming flywheels were replaced with hydraulic dampeners-closers. This allowed the system’s excessive mass to be reduced to 110 kg, of which the weapon body itself accounted for only 20 kg, which, given its dimensions, raises significant doubts. The rate of fire was increased to 400 rounds/min. Other parameters remained unchanged.
Evaluations of the Fiat Mod. 1928 machine gun revealed that it could not serve as a “universal” weapon. For naval use in its initially intended “anti-torpedo” variant, it might have been decent, but as anti-aircraft armament, it was too bulky and immobile. The small magazine capacity and low rate of fire also added disadvantages. Furthermore, with such a long barrel, the system’s internal ballistics were clearly overstressed, affecting barrel life. The same reasons prevented it from being considered for aviation armament.
The Breda S/14 and the Adoption of the Mod. 31
The Breda company submitted its own version of a 14 mm heavy machine gun to the competition, with the in-house designation S/14. Like its competitor from Fiat, the S/14 featured short-recoil operation but was significantly more compact. Unlike the Fiat machine gun, Breda specialists focused on compactness; the Breda machine gun’s overall length was just over a meter with a barrel length of only 600 mm.
To ensure acceptable ballistics for such a short barrel, Breda developed a tremendously powerful 14×102 mm rimless cartridge. Its 59.6 g bullet, equipped with driving bands, more closely resembled an artillery shell by modern classification. The total cartridge mass was 144.66 g and contained 19.5 g of propellant, which accelerated the bullet up to 1000 m/s—very impressive characteristics for that time.
Unlike its competitors at Fiat, Breda developed two parallel versions of the S/14 machine gun simultaneously: an infantry version with water cooling on a massive tripod with handles and a trigger at the breech, and an air-cooled aviation version for installation as fixed forward-firing armament or for defensive turrets. In the turret version, the S/14 machine gun was equipped with an original grip with a full-hand guard and trigger. Feeding for the machine gun was from rather archaic fabric belts from either side of the receiver. The aviation turret version used a metallic disintegrating link belt, housed in a compact drum attached to the receiver. According to some reports, a twin mount of 14 mm S/14 machine guns, installed on an open “Scarff ring” turret, was tested in the air in 1929 aboard a Fiat BR.2 bomber.
However, this little-known Italian weapon prototype also failed to satisfy the military. After comparative trials in 1929, the Breda company never exhibited it again, and mentions of the S/14 in later documents ceased. Apparently, the projectile’s initial velocity of 1000 m/s proved too high to ensure acceptable barrel life. Moreover, the stated rate of fire—only 200 rounds/min—was too low. Although, most likely, this parameter applied only to the infantry version; the aviation version probably had a higher rate of fire. But, one way or another, the 14 mm Breda machine gun remained just an episode in the history of Italian armament.
The Italians’ evaluation of the British Vickers Class D machine gun (12.7×120 mm) remains unknown, presumably its powerful, specialized cartridge was not well-suited for an aviation version. However, the French 13.2 mm Hotchkiss was quite appealing to the descendants of ancient Romans. On the one hand, for its caliber, the French machine gun was light and compact enough; on the other hand, its very powerful 13.2×99 mm ammunition with a heavy 52-gram bullet left the barrel at a lower speed than the Italian prototypes—around 790 m/s—which allowed for hopes of greater barrel life. The two feeding options developed by the French—from rigid cassettes with side feed and from box magazines with top feed—also looked attractive.
The Legacy of the Breda Mod. 31
At the end of 1929, it was decided to purchase a batch of French machine guns for troop trials and the second stage of the competition. Fiat was chosen as the general contractor for the contract with the French, and was also offered to rework its 12.0 mm Mod. 1928 machine gun for the French 13.2×99 cartridge for a more accurate comparison of weapon characteristics with a unified cartridge. In parallel, the Scotti (“Armi Automatiche Scotti”) and MBT (“Mecchanica Bresciana Tempini”) companies joined the competition. Apparently, the Scotti project did not proceed beyond the paper stage. However, the MBT arms company presented its 13.2 mm machine gun prototype in 1931, featuring short-recoil operation, a 30-round box magazine, and versions for infantry (on a wheeled mount), naval (on a pedestal), and aviation use. Data for this weapon, which remained a prototype, is unknown.
In January 1930, Fiat’s armaments division, “Società Anonima Fabbrica Armi Torino” (SAFAT) in Turin, signed a contract with Hotchkiss for the supply of 30 machine guns and 60 spare barrels in the box-magazine version. Later, the contract volume was increased to 80 machine guns plus licenses for weapon production and for the French cartridge.
However, in the summer of 1930, the Fiat conglomerate sold all rights to its arms patents to the Breda company, which also acquired the French contract. The new owners shelved the adaptation of the Fiat-SAFAT Mod. 1928 machine gun to the French cartridge, focusing instead on the licensed production of French machine guns under their own brand. In autumn 1930, Breda signed its first contract with the Regia Marina—the Royal Navy—for the supply of 300 13.2 mm machine guns in twin configuration and 100 in single configuration. In July 1931, the navy accepted the first 50 new heavy machine guns, which received the designation Breda Mod. 31.
The machine gun, which used gas-operated automation providing a rate of fire of 400-500 rounds/min, almost exactly replicated the Hotchkiss design. The barrel, 75.6 calibers or 1000 mm long, like its French prototype, was equipped with transverse cooling fins. From late 1932, the new machine guns began to be massively installed on naval ships in twin and single pedestal mounts with manual aiming. Retractable installations in a sealed container for submarines were also developed.
In smaller volumes, 13.2 mm Bredas were produced for army use on wheeled mounts with folding tripods. Practically simultaneously with the French, the Italians in 1935 switched to using a shortened 13.2×96 mm cartridge, which replaced the older 13.2×99 mm, often confused with the half-inch Browning. The heavy-caliber Breda long remained the basis of short-range anti-aircraft armament in the Italian navy, serving as a base for later 20 mm and 37 mm automatic cannons, essentially scaled up from the successful design. Heavy-caliber Bredas were successfully used in infantry, territorial defense anti-aircraft artillery, and installed on trucks and armored vehicles, remaining in service until the end of the 1940s.
Image and diagram gallery of the Breda S/14
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