Selling this upper I built almost 2 years ago. It is fully working and cycles no problem, though I could never get the hop/rubber/inner setup to work to my satisfaction. I'm by no means a gun tech so didn't have the patience to get this finished. 

This upper consists of the following:

Angry Gun upper receiver (ceracoted)

HAO 13.5" URGI rail

Gemtech dummy suppressor (hides the end of the inner barrel)

Strike industries aluminium fore grip

Replica Geissle scope mount

Vortex strike eagle 1-6 x 24 scope

Replica Trijicon RMR and offset mount

Original MWS dust cover and charging handle

The outer barrel is by Creation I believe 

Internally I'm not positive but I believe it's a 410mm inner (brand and bore unknown), the hop system is almost certainly laylax stuff.  The bolt carrier might be Marui but I'm not sure. 

I can't remember what the muzzle energy was last time I tested but it was way higher than 1 joule.

Price includes postage