Ranger Takedown

 is a quest perk in Fallout: New Vegas. It is acquired by winning a speech challenge from Ranger Andy after he tells you about his multiple leg injuries. It can also be acquired by completing an unofficial sidequest which requires you to check on Ranger Station Charlie and tell him what happened there.

Effects
While holding back and the attack key, the player performs an unarmed attack which will knockdown enemies. Interestingly it can also be preformed with melee weapons as well. (tried it with the bumper sword and an asortment of other melee weapons)

Behind the Scenes
The Ranger Takedown is likely a reference to Walker Texas Ranger (Chuck Norris) famous for his roundhouse kicks capable of taking down nearly anyone.

Bugs
In 3rd person view, the player character will perform a roundhouse sweep, while in 1st person view, the player character simply thrusts their open fist forwards.