Phillip Miles, 57, the pastor of Christ Community Church in Conway, South Carolina, was caught with the rounds when he flew into Moscow's Sheremetyevo airport on January 29. He was later charged with illegal possession and smuggling of ammunition.
Investigators said Miles visited the country on more than 10 occasions, and almost always stayed with his Russian friend in Perm.
The judge said Miles was bringing the rifle rounds to his friend "as they were both keen hunters, and have permission to hunt."
However, she said: "The court is skeptical over the pastor's statement that he did not know he had to declare ammunition being brought into the country - this runs contrary to evidence presented in court."
Miles, his lawyer and defense witnesses have said the cleric's actions were unintentional. His lawyers plan to contest the decision at a higher court, the Moscow City Court, within the next 10 days.
