This paper model is a full size Heckler & Koch HK416 (aka M416) an assault rifle/carbine designed and manufactured by German firearms company Heckler & Koch, the papercraft is created by Hoborginc. There is another version at papercraftsquare: Heckler & Koch HK416 Assault Rifle Paper Model Ver.1.
This model is 1:1 scale, consists of several distinct parts that can be disassembled, and includes a collapsible stock and moveable bolt carrier. In addition to the rifle, some accessories like a foregrip, various ironsights, an ACOG optic, and an AN/PEQ-15 laser/IR module are included. ~via Hoborginc
You can download this paper model template here: Heckler & Koch HK416 (M416) Assault Rifle Free Paper Model Download