I'm from the City of Lost Angels, Kommiefornia.
No, you don't need to register an upper even if your lower is stampped 6.8 spc, and you get a 5.56 or 9mm etc etc upper.
I would like to warn you though, that your have to change the barrel AND bolt to convert it to 5.56, not just the barrel.
Assumption is the mother of all ****ups.
Know what you know, Know what you don't know. -Paul Pedzolt
"Jack of all trades, master of none, though oftentimes better than master of one" -Mynshul
Last edited by AgentTikki; 02-04-2013 at 08:29 PM.