Hearing Protection Act of 2017 This bill amends the Internal Revenue Code: (1) to remove silencers from the list of firearms subject to regulation under the National Firearms Act (NFA), and (2) to specify that a person who lawfully acquires or possesses a silencer under provisions of the federal criminal code meets the registration and licensing requirements of the NFA. Additionally, the bill amends the federal criminal code: to preempt state or local laws that tax or regulate firearm silencers, to exclude a muffler or silencer from the list of firearms subject to regulation, to eliminate mandatory minimum prison terms for a crime of violence or drug trafficking offense in which a defendant uses or carries a firearm equipped with a silencer, and to permit active and retired law enforcement officers to carry a concealed silencer.