When the female deputy is firing her pistol at the gunfight in the desert,
she runs out of ammo. Four "clicks" are clearly heard as she continues to try and fire but is out of ammo. Clearly the slide of her pistol is caught in the most rear position, which would block the hammer from getting released. Hence it would be impossible for the hammer to strike the firing pin and make a click noise.
At minute 35, two black SUVs are barreling down the highway towards a barricade of multiple police cars stacked into two rows. However, when the snow plow rips through the barricade, the second row has disappeared.
When Officer Owens uses the rear of his truck to save Officer Torrance during the shootout, the truck's bumper is damaged in a collision with a patrol car. When the truck pulls away from the collision there is no apparent damage.
When Frank is shooting a bad guy on the stairs, the slide is locked back on his handgun indicating he is out of ammunition. Yet a second or two later he fires one more round into the bad guy and the slide locks back again.
At the beginning of the film just before the line "thought he wasn't working today" there is nothing on the brim of the Deputy's hat. Then a piece of beef appears and the Sheriff tells him to take it away.
Sheriff Owens tackles one of the shooters off of the diner roof and shoots him in the head, when they both land there is a halo of blood under the guy's head. The shot cuts away and when it cuts back the blood is gone.
In the cornfield chase towards end, the Camaro's driver side view mirror is broken off when the Corvette rams it sideways. It remains missing for the chase but it is undamaged and returned by the farm machinery strike and when Sheriff Ray handcuffs the walking fugitive to the car in the last scene.
(at around 64 mins) Sheriff Ray Owens goes into Irv's bar to warn the diners and the clock on the wall says 7:21 AM. Four minutes later after the line "time for a turkey shoot" screen fades to black and goes to Figuerola walking down the street with a placard reading 7:10 AM.
During the initial scene of Cortez being broken out of the FBI convoy in Las Vegas, the camera sweeps by a blue street sign showing the action occurring on "5th St." There is no such street sign in Las Vegas, as 5th St. was renamed "Las Vegas Blvd." in 1959. Furthermore, street signs in the City of Las Vegas are green, not blue.
Ray asks to see a gun permit. In Arizona, a person over age 21 may legally carry a concealed firearm or deadly weapon without a permit within the state, but must disclose the fact to law enforcement if questioned.
While in the ambulance Mike and Lewis both talk about the wound in Mike's shoulder being a .50 Caliber wound. First off, the rifle that bad guy sniper used was a Blaser R93 Tactical which is only available in .223 (5.56mm), .308 (7.62mm), or .300WM, not .50 Caliber. Even if the rifle used was a .50 Caliber, the round would have taken Mike's arm and most of the shoulder clean off.
Sheriff Owens threatens Lewis Dinkum with a citation for the huge revolver he carries. The movie takes place in Arizona, which is a legal carry State and where there is no restriction on revolvers, whatever the caliber. No citation could be given unless Dinkum was specifically not allowed to own a firearm based on his record.
When Frank Martinez is engaged in the gunfight on the stairs on the way to rescue his partner, the slide on his pistol locks open (indicating an empty magazine and chamber) just before he fires his last shot. There was no time to carry out a reload as there was only a split second between scene cuts.
Burrell's choice of weapon for the showdown in town was a Colt Walker, a cap and ball black powder pistol from the 1840s. Not only did you not see clouds of black smoke every time he fired, but he never reloaded, a job that would have taken several minutes.
When the sheriff is being dragged in the car through the corn field, he shoots through the open driver's window at the villain. When the villain drops the car with the sheriff a clear shot of sheriff's car shows that the window is closed and there is nobody inside.
(at around 1h 4 mins) Lewis Dinkum starts to use a chainsaw to cut down a utility pole to block the road and says when challenged, "This is the phone and cable. Electricity is over there." When the pole starts to fall - there is a street light on it and no other cables. Cut to a scene on the plane, then cut back to the street where Dinkum climbs the pole to try and make it come down and when the cable snaps, sparks fly everywhere - definitely not phone and cable.
The goof items below may give away important plot points.
When Farmer Parsons is shot, he falls in the same direction that the bullet came from. The momentum of the shot should have knocked him off the tractor in the same direction that the bullet was traveling, towards the right side of the screen.