My grandpa just gave me two H. Schmidt Ostheim 22 revolvers. Model 21 S. One is in pieces (my doing) and the other is completely functional. I know they are not worth much money but I want them both working because he gave them to me. Any general information on these is more than welcome. Are the any diagrams of these available? Or anything that can be done to these guns? I'm not looking to increase resale or anything or wanting to hear it'll cost more than the gun is worth.