About the bill
The Gun Control Act of 1968 (GCA or GCA68) is a U.S. federal law that regulates the firearms industry and firearms owners. It primarily focuses on regulating interstate commerce in firearms by generally prohibiting interstate firearms transfers except among licensed manufacturers, dealers and importers.
The GCA was signed into law by President Lyndon B. Johnson on October 22, 1968, and is Title I of the U.S. federal firearms laws. The National Firearms Act of 1934 (NFA) is Title II. Both GCA and NFA are enforced by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF).
This summary is from Wikipedia.