Everyone in the final gun battle never reload their weapons and just keep shooting hundreds of rounds.
During the showdown on the ranch, Viner climbs up an oil rig. When he gets shot, he falls down and the crash mat is visible.
During the final gun battle, a man screams, "Grenade," but a grenade hadn't been thrown yet.
When Little Dee talked to Ben Arnold before she let, she told him she saw his brother Aaron Arnold kill the deputy and even where the body was, which he found. But when he brought the body in and confronted his brother, he only said that Little Dee saw the deputy at the farm where Aaron was the night before, not that she saw him kill the deputy.