Rangers where issued SCAR's back in 2009, although the current state of the SCAR is up in the air, some say they have been discontinued some disagree.
Here's a little old of a picture, but shows a good impression of a ranger unit issued with SCARs. Mind you they where NOT a deployed unit and the picture was taken at a Nascar race soooo.. Take what you will from this.
http://defensetech.org/2009/05/26/ra...t-their-scars/