Since October, the bureau’s entire cadre of appeal examiners— about 70 analysts — was redeployed here to help keep pace with waves of incoming background investigations that continued through December when a record 3.3 million firearm sales were processed.

The transfer of examiners, which had left a backlog of 7,100 appeals, is only part of a makeshift reorganization that FBI Assistant Director Stephen Morris said has become necessary to handle a burgeoning workload that expands in the wake of every mass shooting and call for increased gun control that invariably prompt firearms sales binges across the country.

“The last several months, we’ve kind of found ourselves in a perfect storm,’’ Morris said in an interview with USA TODAY. In each of the last six months, the number of background checks has risen steadily, according to FBI records, ending with December’s record with more than a half-million over the previous monthly high posted in the aftermath of the 2012 Newtown, Conn., school massacre.