1. Short title This Act may be cited as the Closing the Bump-Stock Loophole Act . 2. Bump fire stock and other devices designed to accelerate rate of fire of semiautomatic weapon treated in same manner as machine gun (a) In general Section 5845(a) of the Internal Revenue Code of 1986 is amended by striking and (8) and inserting the following: (8) a reciprocating stock, or any other device which is designed to accelerate substantially the rate of fire of a semiautomatic weapon; and (9) . (b) Semiautomatic weapon Section 5845 of such Code is amended by adding at the end the following new subsection: (n) Semiautomatic weapon The term semiautomatic weapon means any repeating weapon that— (1) utilizes a portion of the energy of a firing cartridge to extract the fired cartridge case and chamber the next round, and (2) requires a separate function of the trigger to fire each cartridge. . (c) Effective date (1) In general The amendments made by this section shall take effect on the date of the enactment of this Act. (2) Application to possession on date of enactment Notwithstanding paragraph (1), any person on the date of the enactment of this Act possessing a device described in section 5845(a)(8) of the Internal Revenue Code of 1986 (as amended by this Act) shall, not later than the date that is 1 year after the date of the enactment of this Act, register such device with the Secretary of the Treasury and include with such registration the information required under section 5841(a) of such Code. Such registration shall become a part of the National Firearms Registration and Transfer Record required to be maintained by such section.