Whitewolf The Mauser action became very popular following WWII because of the thousands of surplus military rifles that found their way to the USA. To satisfy the demand for a better grade of rifle many manufacturers began making commercial actions that were, functionally, near duplicates of the military models but with improvements "built in". The FN was one of the better ones. To say that it's a "replica" is probably not entirely correct. It would be like saying that all automobiles are replicas of the Ford Model T.