The first 40 M36s did not make it overseas until September 1944, and entered combat in October 1944. The First and Ninth US Armies used M36s to reequip tank destroyer battalions attached to armored divisions. The 703rd Tank Destroyer Battalion began reequipping on . The Third US Army used them to reequip towed battalions. The 610th Tank Destroyer Battalion (Towed) began retraining on . The first tank destroyer battalion to actually receive the M36 in early September, the 776th, was in transit from Italy to Europe at the time and did not use them in combat until October 1944. The M36 was well-liked by its crews, being one of the few armored fighting vehicles available to US forces that could destroy heavy German tanks from a distance. Corporal Anthony Pinto of the 1st Platoon, Company A, 814th Tank Destroyer Battalion knocked out a Panther at 4,200 yards. Another 814th gunner, Lt. Alfred Rose, scored a kill against a Panther at 4,600 yards, the maximum range of the telescopic sight. However, the Panther's 82 to 85mm thick glacis plate could deflect certain shots from the 90 mm gun at just 150 yards, and the 150mm thick front armor of the Tiger II could only be penetrated in a few hard-to-hit places. By the end of 1944, seven tank destroyer battalions had converted to the M36. The M36 had mostly replaced the M10 by the end of the war.