SPECIFICATION Gun weight, kg 876 (1200) Bore length, clb 51.6 Fire rate, shots/min 12-15 Crew, men 5 PENETRATION TABLE Angle Range, m 100 500 1000 1500 2000 The BR-350A projectile 60° 67 61 55 49 43 90° 82 75 67 60 53 The BR-350B projectile 60° 55 49 43 38 34 90° 66 60 52 46 41

In May 1941, the development of a new 76 mm divisional gun was undertaken by Grabin's design bureau. The idea came from trials of the ZIS-2 antitank gun that was in testing from September 1940. Construction of the ZIS-2 became the base for the new gun, named the ZIS-3. The gun consisted of a new barrel on the ZIS-2 gun carriage. The first prototype had an elevation angle of +45°. The gun carriage wasn't designed for such a powerful gun, so the ZIS-3 was equipped with a muzzle brake of 30% efficiency (i.e. it absorbed 30% of the recoil energy). The gun had a vertical semi-automatic wedged lock, a hydraulic recoil brake, and a hydro-pneumatic reflexive mechanism. The elevation mechanism had two sectors, and the wheels were taken from the GAZ-AA truck. The gun's limber was the unified Limber Model 1942, although limbers from other 76 mm divisional guns were used occasionally.

The first experimental gun was finished in June 1941, and in July it successfully passed trials. In July 22, 1941, the gun was showed to Marshal G. Kulik. He examined the gun but prohibited its mass production. Despite Kulik's order, Grabin was able to place an order through Factory #92. Until the end of 1941, only a limited number of ZIS-3 were produced. Because of a high demand for divisional guns, Stalin allowed production of everything that could fight German tanks even if they were of poor quality and performance. Production of these other weapons lead to low production of the ZIS-3.

Officially, the ZIS-3 was accepted for service from February 12, 1942, and named "the 76 mm Divisional Gun Model 1942." By that time, the Red Army already had at least 1,000 guns.

The ZIS-3 was produced in two factories: #92 and #235 (see table). In addition, in 1944, Factory #7 produced 14 ZIS-3 guns.

In fact, there were three types of ZIS-3:

-with riveted gun carriage and lock from the 57-mm ZIS-2 and a push-button sear;
-with simplified lock and lever sear. Elevation +27°;
-with simplified lock and lever sear. Elevation +37°.

Due to the very low cost to produce the ZIS-3, it was the first gun to be put into mass production around the world.

The ZIS-3 was truly the most famous Soviet gun. Professor Wolf (Chief Engineer of the Artillery Department of Krupp Corporation) wrote in his dairy, "German guns, in general, were superior to guns of other countries with the exception of the Soviet Union. During World War Two, I was testing captured British and French guns. Those tests clearly showed that German guns were superior. It is true that the Soviet ZIS-3 was the best gun of World War Two. Without any exaggeration, I affirm that this gun was one of the most genius weapons in the history of artillery." After seeing the ZIS-3, Stalin said, "This gun is a masterpiece of gun development!"