The Double-Action Revolver is introduced as a current unlock for GTA Online.
To unlock it, you will need to complete a 'treasure hunt' around GTA Online to find this newest weapon. Players should receive an in-game email for your first clue. Find all clues and you will receive this weapon.
That's not all.. once this weapon is added to your inventory, there will a 50 Headshot Challenge in free roam. Complete that for a GTA$250.000 reward plus unlocking it for Red Dead Redemption 2 for PS4 & XBox One. (Notice PC wasn't mentioned..)
Anyway.. this was how I unlocked it based on the clues given to me. Not done very professionally but it's just to show you guys where exactly the clues are.
Some of my friends have mentioned the first clue wasn't the same as mine so there could be a few variations. Do let me know if yours was different from mine, in the comments below, so maybe we can get an idea of how many variations there are.
Hope this was useful!
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