rifle or shotgun.
When a national instant criminal background check is required pursuant to state or federal law to be conducted through the National Instant Criminal Background Check System (NICS) or its successor in connection with the sale or transfer of a rifle or shotgun to any person, before delivering a rifle or shotgun to such person, either (a) NICS has issued a "proceed" response to the seller or transferor, or (b) thirty calendar days shall have elapsed since the date the seller or transferor contacted NICS to initiate a national instant criminal background check and NICS has not notified the seller or transferor that the transfer of the rifle or shotgun to such person should be denied.