What you have is a 'Combat Magnum'. The legal serial number will be found on the butt of the grip frame. If the gun has target grips - as most were furnished with, you'll have to remove them to see it. The letter 'K' is actually part of the serial number, and the K260,000 range is correct for the first of the Combat Magnums. This gun became known as the Model 19 when model numbers began being assigned.

Mark

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