"It's like hitting them with tennis balls!"
Yup.
American tanks were peashooters in comparison to German Tigers and Panthers. The German tanks were much bigger, more heavily armored, and had much bigger guns than their Allied counterparts. Problem with the German tanks was that they were impossible to mass produce and they were huge gas hogs at a time when Germany was desperately low on fuel. This was especially true with the Tiger tank.
Great movie btw. And yes Telly Savalas “Sgt Guffy” was correct when he said firing at them was like hitting them with tennis balls. A US Sherman tank could fire virtually point blank at the frontal armor of a Tiger tank and barely put a dent in it. A Tiger, on the other hand, could easily take out a Sherman almost a mile away.