It appears to be a Model 600. By the serial # it was made in 1936. In the published book, "The History of W. & C. Scott Gunmakers by Crawford and Whatley, pg. 69, it shows an illustration of your shotgun with a brief description. It states the shotgun was made in 5 versions from 1927 to 1946. "The Model 600 (Figure 62) was introduced in 1927 as a non-ejector gun in plain quality only. Webley & Scott supplied the Model 600 in 12, 16, 20 and .410 bores; most guns were made without a rib extension. A number of versions, including the 601 (1937), 602 (1937), 603 (1938) and 604 (1939) were added to the series before production ended in 1946."

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