There are a couple tactical issues in the movie, but they got the weapons right - mostly, the S&W 1917 revolver is the glaring exception.
The American troops are carrying M1 Garands, while the German enlisted carry 98Ks, and the German sniper has a 98K with correct scope and mount. Even better the officers and NCOs have not just M1 Carbines, but correct for the period M1 Carbines with the early l shaped rear sight and the small barrel bands without the bayonet lug.
Brad Pitt carries a S&W 1917 with "sweetheart" grips where a picture is placed under grips cut and polished from plexiglass - a form of soldier gun art that was around at that time. But a S&W 1917 would not have been standard issue for a tank crewman. I suspect it's meant to be a 1917 that Pitt's character has had for a while and, along with the custom holster, is supposed to add to the "old salt" nature of the character.
I also noticed the crew had the later M3A1 sub machine gun with the finger hole in the bolt, rather than a charging handle. It's possible that they could have had A1s in early 1945, but not likely as they were just entered service in late 1944, and it took a while for them to trickle through the system to combat units. Not many M3A1s actually made it into combat in WWII.
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Tank wise they had a good mix of M4 types, something that wasn't uncommon in action where units were sometimes reconstituted and where knocked out tanks (the ones that didn't burn and compromise the armor) were rebuilt at the depot level and returned to service.
Pitt's M4A2E8 is identifiable by the HVSS suspension, wide tracks, 76mm gun and diesel engine, and it's not quite accurate as the M4A2E8 never saw combat in US service. The US Army preferred the gas powered M4A3E8 - which was the same tank, with the same welded hull, T23 turret, M1 76mm gun, and HVSS suspension, but with a Ford GAA V-8 engine.
), and it does show the supposedly only surviving operational Tiger in the world (from the Bovington tank museum in Britain) in action.
