Considering the current lower situation, and the DOJ memo:

When CA banned .50 BMG, it appeared to present an oppertunity to register an off-list lower if that lower was built up as a .50 BMG using one of the .50 BMG uppers that are around.  Once registered, one could convert to semiauto 5.56. Is this correct, or would the .50 BMG AR only be legal as a single shot .50 BMG?
Has anyone tried this?

If you had an off list lower that was built up and registered as a .50 bmg, than you should be able to register it as an AW if it does get updated to he list by DOJ.  At that time we'll have to see if we manage to hand DOJ their asses in court regarding the SB23 banned features.  If we do, than have at it.

.50BMG and AWs are different types of weapons. An AW may be a .50BMG, but being registered as a .50BMG DOES NOT allow the use of AW features (pistol grip, blah blah)

Quoted: .50BMG and AWs are different types of weapons. An AW may be a .50BMG, but being registered as a .50BMG DOES NOT allow the use of AW features (pistol grip, blah blah)

And there you have it.  Another soon to be gaping hole of ambiguity in Kalifornia's gun laws.  Only the fucktards in the Kali court system would allow this kind of lunacy be the way people have to live their lives in order to avoid becoming criminals.