Other mistake: In the final battle where the two rangers are waiting for Upham to bring them 30cal ammo, they fire their rifles through a hole in the wall. At one point two German soldiers are seen dying from the same shot, even though they are at least five meters (about sixteen feet) apart.
Other mistake: When the company makes its first advance up the grassy hill through mortar explosions and flying bodies, as the guy next to Captain Staros takes a turn with the binoculars, watch carefully. You'll see he has them pointed down into the grass, not up the hill where the fighting is occurring. Further, the field has zero visibility from gunsmoke, which would prevent him from seeing anything anyway, even if he did have them properly aimed. (00:47:35)