Making Character Arms Move with Camera

I’m trying to make a first person weapon system with capabilities to third person when not actively shooting similar to Apocalypse Rising’s system.
I’m assuming that this is done by using the actual character’s arm’s instead of a ViewModel like the various FPS guides on the forum show but I’m having trouble actually having the character’s arms move with the camera.

What I’m trying to achieve:

Any help would be very appreciated. (: