Isn't that sideways v sign some sort of up yours thing? Violent rapper rudeness, at any rate.
I have no idea. (I'm sorta out of the rapper loop) I just know I have seen a lot of pics of Joran & Friends using that sign. Could be just a teenage thing.
More here for "HAND SLANG:
http://zimmer.csufresno.edu/~haralds/htmlfiles/gang-signs.html
http://www.hip-hop-music-classic.com/Gang-Hand-Signs-Gang-Members.html