No Congressional Gun Loophole Act This bill prohibits the Capitol Police Board from allowing Members of Congress or their staff to carry firearms on the grounds of the U.S. Capitol or in its buildings. Members and their staff may store firearms in their cars in Capitol complex garages if their possession complies with the firearms laws of the District of Columbia and the firearms are locked with gun locks while on the complex. Current board regulations allow Members of Congress to keep firearms in their offices; the regulations also allow Members and their staff to transport unloaded and securely wrapped firearms within the Capitol grounds. Firearms are prohibited inside the chambers of the Senate and the House of Representatives, as well as in adjacent lobbies and cloakrooms, the galleries, the Marble Room of the Senate, and the Rayburn Room of the House, unless approved by the Sergeants at Arms for security purposes.