NSSF Commends Rep Duncan’s Introduction of the Hearing Protection Act Ammoland Inc. Posted on IMG Jim Grant U.S.A. -(AmmoLand.com)- The NSSF, the firearm industry’s trade association, commends U.S. Rep. Jeff Duncan’s (R-S.C.) introduction of the Hearing Protection Act, H.R. 95. The legislation was introduced with 36 original co-sponsors. The bill would remove firearm suppressors from the list of definitions under the 1934 National Firearms Act (NFA), eliminating onerous and duplicitous background checks. Instead, what is essentially a muffler for a gun would be regulated under the 1968 Gun Control Act (GCA) with the same background check that is required for a retail firearm purchase.