There is something similar. If you double tap left control you lower your weapon. In all honesty though, it really wouldn't make a difference unless they were your friends in the first place. Most likely they are bandits and will shoot you regardless.
Hey I'm joining the Air Force soon and I'm new to this game, only been playing today. My lil brother and I would like to join up with you. Skype: Willrbry Few questions too. What timezone you in? When do you usually play? Do you have other people who play?