Call of Duty: Modern Warfare 3 | The JAK Headhunter Carbine Conversion is a new Aftermarket part introduced in Season 1 for the Rival-9 SMG. The attachment tunes the weapon to be more of an assault rifle, and players can get by completing a few challenges.
How to Unlock the JAK Headhunter Carbine Conversion in MW3
The JAK Headhunter Carbine Conversion attachment can be unlocked by completing five Season 1 Week 1 challenges. The challenges do not have to be done within the first week, but must be done before the season is over to receive the new attachment.
