N.H. Rev. Stat. Ann. § 159-B:5

Notwithstanding any other law to the contrary, a person may not maintain a nuisance action for noise or noise pollution against a shooting range, or the owners, operators, or users of the range, located in the vicinity of that person's property, if the shooting range was established, constructed, or being used on a regular basis as of the date the person acquired the property.