3. Background checks (a) Requiring background checks for purchases of ammunition (1) In general Section 922 of title 18, United States Code, is amended by inserting after subsection (u) the following: (v) (1) Beginning on the date that is 180 days after the date of enactment of the Ammunition Background Check Act of 2018 , no person who is licensed under this chapter shall transfer ammunition to any other person who is not licensed under this chapter, unless— (A) before the completion of the transfer, the licensee contacts the national instant criminal background check system established under section 103 of the Brady Handgun Violence Prevention Act ( 34 U.S.C. 40901 )