Do you use fatebringer? I believe the firefly perk considers those enemies defeated by the explosion causes them to be considered as precision kills.
Just a theory.
yes firefly explosion also counts as precision kills so if you want to raise your handcannon ratio target groups with alot of small enemies get easy headshot plus explosion off firefly get free precision kills
More precision kills than overall hc kills xD Id say firefly kills make that. No other way to explain any of these +61% ratios. Just by thinking how friggin many hits you need to kill like mino or mino major.