The only reference I can find to a Scotti LMG is in MILITARY ARMS OF THE 20th CENTURY - 7th Edition, by Ian V. Hogg and John S. Weeks, where there is an entry (but no photograph) for "Machine gun, System Scotti, Model 28" (manufactured by Isotta-Fraschini SpA. Turin)(caliber 7.7mm [303 British]
"The Scotti light machine gun was one of the range of weapons designed by Alfredo Scotti of Brescia. He was a freelance designer associated, for the most part, with the Italian aircraft firms and most of his weapons were intended for use in air warfare, although he also produced some machine guns and a few light guns for infantry use. The pattern of 1928 was the best of his light infantry guns. It utilized the Scotti patent principle of operation, which is a form of locked blowback. Gas is tapped from the barrel and used to unlock the bolt, which is then carried to the rear by residual pressure in the breech. Both belt and drum feed were offered, but the design was not take up by anyone and few were made. The gun is included here because it shows a different approach to the problem of operating the mechanism. In larger form, as a 20mm cannon, the Scotti system was used by the Italian Air Force in World War II.
Length: 42.00in (1068mm). Weight unloaded: 27lb 0oz (12.25kg). Barrel: 25.00in (636mm), 4 grooves, right hand twist. Magazine: 250 round belt. Cyclic rate: 500rds/min. Muzzle velocity: c.2400 ft/sec (731m/sec)."