This is not legal advice!
What I was advised is the firearm must be taken down to a legitimate claim that what
is in your possession are "Gun Parts". Slide off, barrel out, spring out, firing pin out, and
the parts in a lock box. No ammo is best, but at the very least, ammo in a separate lock
box. Even then, it is your contention that this is not a firearm, but you may be required
to bring it before a Judge for a ruling.
The rest of the advice i was given...avoid Maryland, New Jersey, and New York.