The 5cm KwK 39 L/42 was completely ineffective at that range, but in desperation Oberleutnant Zachariae-Lingenthal ordered his Pz.IVs to fire 7.5cm Sprenggranate 34 (HE) rounds at the T-34s. Since the T-34s had been committed straight after a long approach march, they were still carrying reserve fuel drums on their back decks, which could be set alight by shell fragments. A lucky hit or two convinced the Soviets to pull back.22
Despite the near invulnerability of their armour to German 3.7cm and 5cm guns, a number of T-34s and KV-1s were immobilized by hits on their tracks and then abandoned by their crews. After suffering nearly 50 per cent losses, Ogurtsov broke off his amateurish attack. The Soviet 10th Tank Division lost forty-six tanks in their first battle with 11.Panzer-Division, but knocked out five German tanks and several anti-tank guns.23 After the action, Zachariae-Lingenthal inspected some of the abandoned T-34 tanks, alarmed by its superior firepower and armoured protection and later wrote, ‘this was a shocking recognition to the German panzer and panzerjäger units and our knees were weak for a time.’24Meanwhile, Kirponos tried vainly to bring up more of his mechanized corps in order to comply with the Stavka-directed counteroffensive on the morning of 24 June, but only the 15th and 22nd Mechanized Corps were in any position to do anything. Von Kleist was gradually feeding more armour into the battle as the Soviet border defenses were eliminated, but he initially held back the 9.Panzer-Division and his four motorized infantry divisions. This was an important command decision – throughout the Battle of Dubno, the Germans maintained strong mobile reserves, while Kirponos committed each formation as it arrived with nothing left in reserve to deal with enemy breakthroughs. Due to poor Soviet radio security at the division level and below, the German 3rd Radio Intercept Company was able to detect Soviet armour units moving toward the border. Although army and higher-level units used good encryption on their radio nets, the tank regiments and divisions employed simpler ciphers that the Germans could break and often failed to change frequencies and call signs for days after compromise. Soviet tank units also had a bad habit of calling for fuel supplies just before launching an attack, which provided German intelligence officers with a valuable indicator.25
Thus poor Soviet radio procedures in tank units handed another advantage to the German panzer divisions.Not surprisingly, no grand Soviet counteroffensive materialized on the morning of 24 June, since neither the 15th nor 22nd Mechanized Corps were ready to attack. Instead, Kühn’s 14.Panzer-Division attacked eastward toward Lutsk at 0800 hours, supported by bombers from Fliegerkorps V. Kühn’s panzers brusquely pushed aside a Soviet rifle division blocking the road to Lutsk, but then ran straight into Moskalenko’s 1st Anti-tank Brigade west of Lutsk. Moskalenko’s unit was caught with its guns still limbered in column, enabling the panzers to shoot up his lead battalion, but once the rest of his unit deployed on line, the German tanks were vulnerable in the open. The Soviet anti-tank gunners were easily capable of penetrating the Pz.III and Pz.IV tanks at 1,000 meters or more, and it was only the lack of supporting infantry or tanks that prevented Moskalenko from giving 14.Panzer-Division a very bloody nose. As it was, both sides suffered significant losses in this first major duel between panzers and Soviet anti-tank guns. It was not until 1400 hours that the 22nd Mechanized Corps was finally ready to attack, and then only with part of the 19th Tank Division. Bravely charging, a battalion of forty-five T-26 light tanks struck the left flank of the 14.Panzer-Division near Voinitsa and briefly regained some ground. However, the Germans were merely withdrawing to regroup and at 1800 hours they struck back with a combined-arms attack that shattered the 19th Tank Division. Not only were most of the division’s light tanks lost, but the division commander was wounded and all three regimental commanders were killed or captured, as well as the artillery commander. The remnants of the Soviet division fell back in disorder toward Lutsk, along with Moskalenko’s anti-tank brigade. During the retreat, Kondrusev was killed by German artillery fire, leaving the 22nd Mechanized Corps leaderless.