1. Short title This Act may be cited as the Bumpstocks and Acceleration Devices Act . 2. Bump-stock-type devices treated as machineguns (a) In general Section 921(a)(23) of title 18, United States Code, is amended— (1) by inserting (A) before The ; and (2) by adding at the end the following: (B) In such section 5845(b) as applied to this chapter— (i) the term automatically as it modifies shoots, is designed to shoot, or can be readily restored to shoot, means functioning as the result of a self-acting or self-regulating mechanism that allows the firing of multiple rounds through a single function of the trigger; (ii) the term single function of the trigger means a single pull of the trigger and analogous motions; and (iii) the term machinegun includes a bump-stock-type device. . (b) Definitions Section 921(a) of such title is amended by inserting after paragraph (29) the following: (30) Bump-stock-type device The term bump-stock-type device means a device that allows a semiautomatic firearm to shoot more than one shot with a single pull of the trigger by harnessing the recoil energy of the semiautomatic firearm to which it is affixed so that the trigger resets and continues firing without additional physical manipulation of the trigger by the shooter. (31) Semiautomatic firearm The term semiautomatic firearm means any repeating firearm that— (A) utilizes a portion of the energy of a firing cartridge to extract the fired cartridge case and chamber the next round