85 mm air defense gun M1939 ( 52 - K ) The 85 mm air defense gun M1939 ( 52 - K ) ( ) was an 85 - mm Soviet air defense gun , developed under guidance of leading Soviet designers M . N . Loginov and G . D . Dorokhin . This gun was successfully used throughout the German - Soviet War against level bombers and other high - and medium - altitude targets . In emergencies they were utilized as powerful anti - tank weapons . The barrel of 52 - K was the base for the family of 85 - mm Soviet tank guns . Crews of 85 - mm AD guns shot down 4 , 047 Axis aircraft . The mean quantity of 85 - mm ammunition required to shoot down one enemy plane was 598 rounds . After the war some 52 - Ks were refitted for peaceful purposes as anti - avalanche guns in a mountainous terrain . Virtually every country behind the Iron Curtain received this gun after World War II for their air defense . In the Soviet Union itself , these guns were largely superseded by the 100 and 130 mm guns . Description . Adopted in 1939 , the 85 - mm M1939 , like its counterpart the 88 - mm gun , was meant for air defense . Like many anti - aircraft ( AA ) guns of the era it was provided with antitank ammunition in the event a tank should appear . Organization . 85 - mm M1939 guns were organized into heavy anti - aircraft regiments of 16 guns . The regiments were organized into divisions of the field anti - aircraft forces . Tank guns . By 1942 , the 76 . 2mm F - 34 tank gun of the T - 34 medium tank was found to be lacking in range and penetration compared to the German 75 mm Pak 40 anti - tank gun , now mounted on the Stug III and Panzer Mk IV , and markedly inferior to the 88 - mm gun of the Tiger I . Military planners directed the design bureaus of both Gen . Vasiliy Grabin and Gen . Fyodor Petrov to modify the 85mm anti - aircraft gun for use as an anti - tank weapon . Petrov ' s bureau developed the D - 5 85mm gun . Though much too large for the T - 34 turret , it could be mounted in the chassis of the SU - 122 self - propelled gun to create a tank destroyer . This was done , and the SU - 85 tank destroyer went into production . Meanwhile , efforts were underway to redesign the T - 34 turret to make it large enough to accommodate the bigger gun . Grabin , who had been working on the ZiS - 53 at Joseph Stalin Factory No . 92 in Gorky near Moscow , was reassigned to the Central Artillery Design Bureau ( TsAKB ) in Moscow . His project was turned over to 23 - year - old A . Savin . A third team led by K . Siderenko was assigned to yet another 85mm gun project , and developed the S - 18 , to be used in the modified T - 34 turret . The resulting guns were tested at Gorokhoviesky Proving Grounds near Gorky , with Grabin ' s ZiS - 53 winning the competition . However , the new T - 34 / 85 ' s turret had been designed to accommodate the already - available D - 5 gun , and did not mate properly with Grabin ' s gun . The T - 34 / 85 tank went into production making use of the D - 5 gun ( designated D - 5T , for " tank " ) . Savin was put to work modifying Grabin ' s gun to fit the new turret and incorporate other improvements . His initial was added to his gun ' s designation in recognition of his contribution : the ZiS - S - 53 . The T - 34 / 85 Model 1944 included an improved 3 - man turret layout . It went into production in the spring of 1944 . Later tests against captured German tanks found that the tank gun developed from the 85 - mm AA gun , though an improvement over the 76 mm gun , still lacked the firepower of its German competitors . A new antitank gun was then developed , the 100 mm field gun M1944 ( BS - 3 ) .