Development and improvement of Palosha submachine gun

Giovanni agnelli, the later manager of Fiat Company, gave up the method of lubricating the combustion chamber and cut a longitudinal groove on the combustion chamber to solve this problem. Its principle is to let a small amount of gunpowder gas leak into the bore, so that the shell is in a "floating" state in the bore, thus reducing the resistance of shell extraction and avoiding the shell sticking to the bore. He applied for this patent, which was widely used in later weapon design. In the future, the famous HK G3 rifle also adopted this grooved bore design. However, Agnelli's design and patents were taken over by Ansaldo shortly before the First World War, while the S.I.A. machine guns did not develop into practical weapons until 1920s, and only a few S.I.A. machine guns were purchased by the Italian army for training. Due to the small number, S.I.A machine guns have become extremely rare now.

Levi's Mod. 19 15 is completely different from Levi's Mod. 19 14. Just like the miniature model of Agnelli's S.I.A machine gun, it also adopts a fixed air-cooled barrel and feeds bullets from above. The working principle is delayed recoil, and the bolt is heavy. Because Levi has not participated in the design of S.I.A. machine guns, some people think that Willer Palosha Mod.1915 is actually a copy of S.I.A. machine guns.

Although we all say that Willa Palosha Mod. 19 15 is the first submachine gun in the world (while German MP 18 is defined as the first "practical" submachine gun in the world), this is because it is the first fully automatic light weapon to fire pistol bullets in succession, and it is actually Willa Palosha mod.1.

Willer Palosha mod.1915 "submachine gun" actually consists of two parallel guns, each with a shovel handle and a button trigger. Willer Palosha is short, but the total length is only 2 1 inch, and the total weight after loading two magazines full of 25 bullets is about 15. But its overall design is like a heavy machine gun, not a light assault weapon. Wheeler Palosha Mod. 19 15 used on the ground is equipped with bipeds, and some machine guns are also equipped with square shields.

The action principle and function of Willer Palo Shamod.1915 are completely modeled after the S.I.A machine gun, and the gun chamber is completely closed before the bullet is fired. Later, most submachine guns were designed with heavy bolts and unlocking methods for hitting. As long as the power of the bullet is not too great, the freestyle bolt is simply adopted, and the inertia locking is realized by using the weight of the bolt. Although the bolt of Willer Palosha Mod.1915 is bulky, it does not rely on inertial locking itself, but on the basis of "Brich principle", it delays the unlocking time through the oblique locking groove on the inner surface of the tubular shell and the delayed protruding bamboo shoots on the bolt. Brich, an American naval officer, observed the launching process of naval guns and found that the locking mechanism with heavy ammunition was not easy to bounce off than that with light ammunition. From this, he came to the conclusion that when the metal surface is under great pressure, the adhesion between them will be greater than the friction, which is called Brich principle.