UPDATED: B. Todd Jones, director of the Bureau of Alcohol, Tobacco, Firearms and Explosives, confirmed this morning that he is leaving that post, nine days after a leading national gun rights organization called on him to step down or be fired primarily because of the controversy over the agency’s recent proposal to ban a popular type of ammunition for modern sport-utility rifles. Jones, who is departing March 31, was appointed director of the scandal-plagued agency in 2013. Last week, the Citizens Committee for the Right to Keep and Bear Arms called for his resignation or dismissal in the wake of...