how much is this guy likely to get hassled by cops and anti-gun nuts?

[monsignor]

Is it a really big hassle to register firearms restored from virtually nothing?

And what if it's been under water (in a river or lake) so long the serial number's gone?

[Baron]

Is it a really big hassle to register firearms restored from virtually nothing?

And what if it's been under water (in a river or lake) so long the serial number's gone?

Monsignor,
First, registration is not really an issue except in five or six states (New Jersey, for instance) that have absurdly strict laws for anything involving guns. Mere possession or ownership is not a problem. More strict requirements may apply for subsequent sale or transfer.

As to serial number, same basic rule applies. A gun is not required to have a serial number for mere ownership. Sale or transfer will usually require one. Some states (e.g. California) have a system by which a serial number can be acquired.

That guy had a lot of confidence even to attempt that restoration!

Regards,
Baron