When Nancy is talking to Vaneeta in the kitchen, the towel hanging on the oven handle disappears then reappears throughout the scene.
When Nancy shoots at the target, you hear her fire 3 rounds, yet there are already holes in the target. You hear a fourth shot and there are five holes, five shots and there are six holes. You then see Nancy fire the sixth and final round from the revolver, but the target already had six holes in it.
When Nancy is talking to Heylia in the kitchen the red pan disappears and reappears behind Nancy in the scene.
When the holes appear in the target at the shooting range, smoke is visible rising up and away from the holes revealing that they are made by using explosives and not by using actual projectiles.
When Nancy shoots the revolver, there is absolutely no recoil, even though the weapon is at least a .38 caliber weapon.
When Nancy is learning to shoot at the range, you can see where the production company has pre-punched the holes in the target. They are blacked out, but turn white when they are supposedly hit. You can see that there is no hole made in the target, and that the hole is still backed by white paper.