 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.