Tell me what state you live in, and I will tell you if you broke a law.
I live in Washington. I inherited guns from people in Arkansas, who either built them or bought them on the private market without any paper trail in a variety of other states. I'm sure the serial numbers have somebody's name on them from an original purchaser, but there is no record of transfer from that person to anyone in my family. Family lore is that some of them were bartered.
I contacted my local PD about this and was assured that it was legal to own them, legal to transport them across state lines, and did not require that I notify anybody about the transfer or ownership.
You were given bad legal advice. You are also a felon under Washington State law...
http://app.leg.wa.gov/RCW/default.aspx?cite=9.41.113The relevant quote, pertaining to yourself...
"(1)
All firearm sales or transfers, in whole or part in this state including without limitation a sale or transfer where either the purchaser or seller or transferee or transferor is in Washington, shall be subject to background checks unless specifically exempted by state or federal law. The background check requirement applies to all sales or transfers including, but not limited to, sales and transfers through a licensed dealer, at gun shows, online,
and between unlicensed persons."
I did peruse that page for an exception, but I don't think it's there, because section 3 is pretty specific...
"(3) Where neither party to a prospective firearms transaction is a licensed dealer, the parties to the transaction shall complete the sale or transfer through a licensed dealer as follows:"
Arkansas is different, however, as there appears to be no restrictions on the sale and transfer of a long gun from one unlicensed person to another. Which, honestly, I find to be strange...
http://smartgunlaws.org/category/state-private-sales-of-guns/So while you might have a legal argument to cover you, if you owned all those guns before moving to Washington State, I'd say it's still in your interests to get your weapons recorded.