Okla. Stat. tit. 21, § 1290.6

PROHIBITED AMMUNITION Any concealed or unconcealed handgun when carried in a manner authorized by the provisions of the Oklahoma Self-Defense Act and when loaded with any ammunition which is either a restricted bullet as defined by Section 1289.19 of this title or is larger than.45 caliber or is otherwise prohibited by law shall be deemed a prohibited weapon for purposes of the Oklahoma Self-Defense Act. Any person violating the provisions of this section shall be punished for a criminal offense as provided by Section 1272 of this title or any other applicable provision of law. In addition to any criminal prosecution for a violation of the provisions of this section, the licensee shall be subject to an administrative fine of Five Hundred Dollars ($500.00), upon a hearing and determination by the Oklahoma State Bureau of Investigation that the person is in violation of the provisions of this section.