I finished the upper tonight, and mounted it on my DMR lower just for grins:

The upper consists of:
- a BCM complete flat topped upper receiver, BCM BCG, and BCM Ambidextrous Gunfighter charging handle, with BCM 20" gov't profile 1:7 barrel, "F" marked fixed front sight, and A2 flashhider.
- a Knights Armament Co. M5 RAS hand guard system.
- a MaTech rear BUIS
- a Trijicon 4x32 BAC ACOG
- a AAC 3-prong flash hider (not yet mounted) so that I can mount my AAC suppressor.
On order:
- a Colt carry handle with A2 sight. (Just in case I want to go full retro.)
- a Colt complete lower with A2 buttstock.
I'm going to cheat a little and put a Geissele trigger in it. But it should be a pretty cool full sized AR when it's all finished.