20 x 99 mm R ShVAK
20 x 99 mm R ShVAK – introduced into the Red Army's armament in 1936, primarily for the 20 mm Shvak air cannon during World War II and possibly for the Berezin B-20 air machine gun used shortly after the war. The ShVAK machine gun was used to arm, for example, the I-153P, I-16, Yak-1, Yak-3, Yak-7B, LaGG-3, La-5, La -7, Pe-3 and some versions of the Il-2 Sturmovik. Marking at 12 o'clock "513" and on 6 o'clock the year of manufacture (in this case "44" - 1944).
"513" – Rostov-on-Don plant/Omsk plant. In 1916 the Austrian-Russian company Zest for metal and galvanized goods was founded as a joint stock company. On 15 May 1927, the state enterprise "Email' posuda" for the production of enamelled goods was founded on its foundations. Between 1940-41 the plant is handed over to the People's Commissariat for Munitions and is renamed Plant No. 513. It produces gas masks, 20 x 99 mm ShVAK cartridges, artillery ammunition and enamelled goods. The production of enamelled goods is evacuated to plant No. 78 in Chelyabinsk. Probably so that the Germans would not have potties. After the war, gas stoves, parts for agricultural equipment and surgical instruments were produced here. Since 1966, the plant has been producing televisions and is currently concentrating on military ship equipment.