The Stone Hatchet, a weapon we revealed back on July 24th when the After Hours update released, has been added to Grand Theft Auto Online and is unlockable in a similar manner to the Double-Action Revolver.
To unlock this hatchet, keep an out for a text message from Maude for Bounties. Whether these bounties are captured dead or alive, successful completion unlocks the location where the Stone Hatchet is hidden. Once you have received the hatchet, there is $250,000 up for grabs – all you have to do is complete the kills challenge for the weapon. In addition to receiving the weapon and 250,000 GTA$ in GTA Online, this weapon will also be linked to your Social Club account and available for you in Red Dead Redemption 2.
Check out this video by GTAseriesVideos, which shows how to unlock the Hatchet.