1) this is probably one of the worst mistakes in film history, near the beginning of the 8 man rescue, there is a scene of the men walking in a field, if you count there are 8, when Vin Diesel is shot there is another scene just like it (actually it is the same scene because you can see a farmhouse that was in the shot in both scene's) and there is still 8 men
2) The last battle scene were they are defending the bridge, the sniper apparently sees two Tiger tanks, the date is June 13, 1944 (D-Day+7) there was not a single tiger tank 100 miles within Normandy for the first month.
3) Also near the beginning Pvt. Rieben is complaining about saving Ryan, well if you look closely they are all grouped together, that would not happen, they would all keep a distance because a MG-42 or a mortar round could take them all out.
4) I'm not 100% sure but in the D-Day landing, it said Dog Green Sector, well I'm pretty sure that that wave was not the first and Tom says "1st wave ineffective"
5) at the end when the tank is coming across the bridge and the P-51 blows it up you can see that there are no bomb or rocket racks on the wings, However, some P-51's did have armor piercing rounds, but it would have taken a lot, and you don't see a hell or a lot a bullets hitting it, although it coulve been a lucky shot.
6) the info on the tiger tanks is incorrect, miller jumps on the front and shoots into the looking hole at the front, this was reinforce glass, 6 inches of, could sop a high powered rifle shot at . blank. ideal for protecting the men inside. an american jumps on the top and opens the door, throws a grenade in and shuts it. the locking mechanism is on the inside for this very reason and would never have happened.
7) There were no reports of any American units challenging a Tiger tank, only the British sucessfully defeated a tiger tank.