My reply is a little different...
...because I have a registered M2 and I'm friends with the local sheriff. I would strip it and keep all the parts ( in this case I can have all the spares I want , If I sell my gun and have no M2 , then I can't have all the spares ) and turn the reciever over to the sheriff. He will do the fed contacts and see if it belongs to someone . If it's been stolen , then I would turn over the rest of the parts and the guy would get his property back. I've taken two M-16s and a 1928A1 Thompson off the streets so far. The M16s were stolen govt. property from the '60s , but they never wanted the rest of them , so I sold them to fund my hobby. The Thompson was supposed to be a cut-up import , but it never saw a torch. The feds tried to go after the importor and the dealers who sold it , but they had long sence died or closed up.
I know if one of my babies were stolen and one of you found it , I would like to have it returned , not cut up.
Chris