Vietcong, the image name is M14prototype.jpg or something like that, so that's my guess - it's an M14 prototype.
Here's one that probably just wierd enough for everyone to know:
It is Italian, not related to the desert eagle (although it was chambered in some of the same cartridges). It is a revolver that uses the recoil to rotate the cylinder and recock the gun.
http://en.wikipedia.org/wiki/Mateba
One of the few pistols I've been able to fire in the UK I'll let someone else get it.