Revealing mistake: When Angel Eyes shoots Stevens, he does so by firing mostly forwards, plus a few degrees upwards. This causes the soup in the bowl on the table to blast upwards, and the bowl itself breaks apart. However, the gun doesn't appear to be aligned with the bowl or the soup in a way that would cause it to be affected by the bullet being fired, especially seeing as how it was aimed at Stevens' head. (00:14:20)
Revealing mistake: Towards the beginning of the movie, Angel Eyes rides up to a house where he has to get information from a man inside and then kill him. After Angel Eyes kills him at the kitchen table, his son runs down some steps behind Angel Eyes in the background with a rifle in his hands. Angel Eyes pulls out his revolver, turns around quickly, and shoots him dead. Take note that the pistol is not pointing directly at the boy as he is firing it. (00:14:30)
Revealing mistake: When Angel Eyes has finished paying the legless man for information, the legless man hops into the saloon. Notice he has two shadows, revealing the presence of stage lighting. (00:25:08)
Revealing mistake: When Blondie is to be hanged by Tuco, and saved by an extremely lucky hit by a Union mortar, you can see that the wall that will be hit by the grenade has been blown to pieces at least once before; the bricks have no mortar between them, and there is a large circular scorched area on the brick wall. (00:47:10)
Revealing mistake: When the cannon fires at the hotel, in the shot of the room that Tuco and Blondie are in, it explodes; Tuco appears to have been replaced with a stunt double. The man can also be seen bracing for the explosion. (00:49:11)
Revealing mistake: When Tuco makes Blondie march through the desert, there is a shot at the very beginning and Blondie looks over his shoulder, feeling the strain of the desert. Then the camera focuses on Tuco and in this shot, you can see the tracks in front of his horse from a previous take. (01:00:18)
Revealing mistake: When Tuco is about to shoot Blondie in the desert, and the Army wagon is seen approaching, the driver can be seen sitting far back in the rear of the coach wearing a hat. (01:06:33)
Revealing mistake: When Tuco climbs back onto the train after he uses it to cut off his chains, the film appears to have been sped up, as his bodily movements appear unnaturally fast. (01:56:40)
Revealing mistake: After the explosion blows a hole in the wall and Tuco joins the procession of people flowing down the street, when the shot switches to face the characters you can see that the 'woman' in a blue dress in the wagon is actually a man. (Time is for the extended version of the film). (01:59:15)
Revealing mistake: When Tuco is trying to avoid Blondie firing at him with the cannon, there is a shot of him running while an explosion occurs next to him, followed by another shot of him leaping to the ground and rolling over. In both of these shots, Tuco is replaced with a stunt double. (02:36:06)
Revealing mistake: When Tuco first enters Sad Hill Cemetery, you can see the dual tire track ruts left by the dump truck that brought in the sand to make the grave mounds. (02:36:35)
Answer: There's a show called "Hollywood Weapons: Fact or Fiction" which dealt with this exact question (s01e03). Blondie is roughly 200 yds away. In the show the host didn't hit the rope, but only missed by an inch on his first attempt. I definitely think an expert Sharps Rifle shooter could make the shot. The issue however, is the bullet would most likely not actually slice the rope apart as seen in the film (they fired the Sharps at point blank and the rope remained partially intact still). They also tested shooting a hat off someone and (as expected) the bullet just goes right through the hat without lifting the hat at all.
Bishop73
That was another thing that puzzled me. On several occasions in this film, Tuco is suspended from a rope, and Blondie cuts the rope by firing a bullet at it, (I think Clint Eastwood repeated the trick in "The Outlaw Josey Wales"). But if you fired a bullet at a rope holding a (rather large) person like Tuco (or a similarly heavy weight), even at close range, would it really sever the rope? I will have to look out for "Hollywood Weapons Fact Or Fiction." I hope they only used a dummy or a model to re-create the shooting feats. I don't think I would have liked to have been hanging on a rope while somebody fired bullets at me to see if this would sever the rope, or to stand there while they fired bullets into my hat to see if they could lift it off my head.
Rob Halliday