Re: Weatherby Mark II 22
You've got a winner. As mentioned earlier these were first made in Italy, by Beretta if I remember correctly, and then in Japan. I've had one for over 40yrs. and it is about a 1" gun at fifty yards with crap ammunition. The trigger has quite a bit of creep but the creep is smooth. Reliability has never been an issue.
If yout friends father did not show you, disassembly is a bit different. Remove the pin at the rear of the receiver and then pull the barrel/receiver group forward about one-half inch. To remove the bolt pull the operating stub out of the bolt and the bolt will fall free from the receiver.
As with all things rimfire, got to RimfireCentral.com. These guys know their stuff. The value of these is now in the +/- $500. range and the correct scope will add value.
You have a very well finished, adult scaled, .22. Mine has given me tens of thousands of rounds of enjoyment. Do not lose the magazine. They are difficult to find and quite expensive.
Enjoy.