Automatic weapons

Question
Hello,
  I have a question regarding automatic weapons. Correct me if I am wrong, but it is illegal to own an automatic firing gun registered after the date of May 19th, 1986. Now say if I were to buy a WWII era gun, such as a PPSH, and convert it into an automatic weapon, what is the legality of that? I'm still a little confused on many of the legal issues revolving around that. Any input would be appreciated greatly!
         Thank You!

Answer
Hello Adam.
  I cannot inform you, nor would I seek information from, anyone but the ATF&E. When I have a question regarding legalities, which at times are mind boggling, I ALWAYS call them. I ask my question, and they research it. I generally hear back in a few days. You can now ask questions at www.atf.org.
  I have fired one with the 35 round magazine. It is an exhilarating experience.
Thank you for asking for me, Charles Gage.