The 629s were introduced in late 1979 and shipment of the 6" guns to the public started in 1980. Your N779xxx gun could have been shipped around May or June of 1980. The 4" and 8 3/8" were introduced in 1981. The -1 change started in 1982 and about the same time period the alpha-numeric serial numbering system was introduced. The guns that are desirable to the collectors will be P&R with an "N" serial prefix. The 4" and 8 3/8" barrel lengths are harder to find. Many of these guns were shipped with a Mahogany presentation case until 1983.
629s - Google Photos
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