When Jesse accepts Walt's offer and disconnects the call we can see clearly the time on his phone moves from 3:57 to 3:58. In the following scene as Hank is waiting for his killers, the time is 3:07.
Hank's tie straightens out while his supervisor talks to him at the elevator.
The cousins meet an arms dealer in a semi truck. On entering the vehicle, the sun is almost directly in line with the vehicle. Two minutes later when the cousins leave the vehicle, the sun (and the attendant shadows) have moved through about 15 degrees or one hour.
When cousin #2 guns down the innocent bystander, there is a brown Honda SUV to the right of the blue pickup truck. After Hank kills cousin #2 and the camera pulls away for the wide shot, the brown Honda is gone and its spot in the parking lot is empty.
At 46:12 when Hank shoots the assassin the assassin is seen falling to Hank's left side but when the scene changes at 46:16 the body is lying to the right of Hank.
Bullets are incredibly hot once fired. The cartel member would not be able to remove the bullet from the truck driver's vest without wearing gloves.
After Hank kills Salamanca, the ax falls next to him and embeds itself. The pavement is too hard for this. It would have simply bounced off once dropped.
Leonel did not push the Jeep off of himself after Marco shifted it out of reverse. Marco put the Jeep in Drive, not neutral, meaning it would've crept forward at low speed on level ground. It was just enough to get the Jeep off of him and then it rolled forward until striking another parked car, at which point it couldn't move forward anymore, just the same as it couldn't move backwards after being pinned against the parked cars and Lionel.
When Hank picks up the sample cartridge dropped by the assassin, one can see that the primer has been struck, making it an obvious dummy round. True dummy rounds use unstruck primers that have been popped by flaming the inside cup, and sand to replace the propellant.
After the first assassin is disabled by Hank, the second pursues Hank by following his blood trail. This one hears something, turns, and fires two rounds into a by passer. A woman then screams and he whirls to her a tries to shoot her as well. Instead the gun clicks. The pistol's action is open because the weapon has fired its last shot. BUT if the action is open, the hammer is all the way back, held there by the open action. Therefore, the weapon can NOT click. The clicking sound would only happen if the action were closed and the hammer/firing pin hit a bad round for a misfire.