Unpapered firearms were the joy of the tailgaters outside some shows I attended in the 80's. Never even touched any of them for fear of a trap being set. Saw M-60s, M-79s, BARs, Thompsons and even some AKs. Prices were good, but not good enough to want to take a trip to jail. I enjoy my freedoms way too much. One was at a U.S. Army reserve base.