Any help in Id'ing my upper?

[Klacktor]

I have what I believe to be an original CMMG mod4sa in an 18'" Barrell length (full length Gas system) the upper that came with it when I purchased it used second hand is completely unmarked. Does this sound typical on a cmmg upper to you? since then the rifle has changed form markedly but Im curious as weather or not the upper is CMMG as well.

 

[TSU45]

My now gone CMMG upper from 2007ish was keyhole marked. That's all I can tell you.