I thought I understood U marked gun or * one too. This is Red Label I have on GB showed a lot more issues than normal. I thought it might have been extensively tested. It even looked like it may have been a factory reblue. So I contacted Ruger Records......this is their response…."Serial number 400-07867 is a used Red Label, RL-2026, 20 gauge, Skeet & Skeet. Manufactured and shipped in September 1979 and it sold to Orgill Brothers & Company, Inc. in Memphis, Tennessee. Returned in June 1985 and shipped in September 1985 to Buckeye Sports in Canton, Ohio. Returned in February 1989 and shipped in June 1989 to Rody's Gun Shop in Newport, New Hampshire. Our records do not reflect additional information."