Orange Park man accused of selling machine gun conversion devices pleads not guilty Updated: Tags: JACKSONVILLE, Fla. – A Clay County man accused of selling unregistered devices online that can convert semiautomatic firearms into machine guns pleaded not guilty Monday in federal court to a single-count indictment. The not-guilty plea came hours after the U.S. Attorney’s Office for announced a federal indictment charging Kristopher Ervin, 41, of Orange Park, with possession of an unregistered machine gun conversion device. Ervin faces up to 10 years in federal prison if convicted of that charge and $250,000 in fines. Ervin was ordered to remain in custody pending the outcome of an April status conference. A judge agreed with an argument from the government that Ervin, the brother of a Jacksonville police officer, was a danger to the public and posed a flight risk.