Glad to help: The serial number is located on the bottom of the aluminum metal frame of the grip, that is, the very bottom under the grip. Point of interest, the RG-23 six shot .22 caliber revolver, was made in two barrel lengths, 1.75 inch and 3.38 inches. It is a cheap, yet fairly well made revolver, and the parts, and usually the whole gun is/are made by Rohm Gmbh in Sontheim/Brenz, Germany. It can be worth between 50 to 75 US dollars depending upon condition.
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