 Fighting against Panther tanks in Normandy quickly demonstrated the need for better anti-tank firepower, and the 76 mm M4s were deployed to First Army units in July 1944.Operation Cobra was the combat debut of the 76 mm gun-armed Sherman, in the form of the M4A1(76)W. General George S. Patton's Third Army were initially issued 75 mm M4s and accepted 76 mm-armed M4s only after the Battle of Arracourt against Panther tanks in late September 1944.The higher-velocity 76 mm gun gave Shermans anti-tank firepower at least equal to most of the German vehicles they encountered, particularly the Panzer IV and StuG III.