Continuity mistake: In the grand finale shootout scene, the flak guards on the truck-mounted machine gun Rambo uses are immediately covered in blood and gore from the soldiers he shoots in the truck. There is at least one shot in the midst of the massacre where the panels are squeaky clean, then re-appear blood-soiled again in the subsequent shots.
Continuity mistake: When the boat is stopped by the pirates they throw two hooks onto the boat to secure the boats. Later in the scene, when Rambo is about to leave he throws one hook off but not the other. Despite this the boat seems to no longer be attached to the pirates boat.
Continuity mistake: After Rambo eviscerates Major Tin and kicks him down the hill, in the next shot the blade of his knife is totally clean with not a smear of blood or gore on it.