Your gun is a 700 . As to proof dates .Prior to 1975 the date stamp was crossed pikes with the code letters AB=1950 to ZB=1974 .1975 to 1984 a circle with letters AB=1975 to KB=1984 .Webleys were numbered at jointing stage and would have been proofed within a couple of weeks of this . The barreled action may have stood for a while prior to finishing or the finished gun been held in the warehouse befor sale to a shop and subsequent customer as a new gun . It is therefore possible that a gun with a eg. 1975 proof date may not have actually been sold until 1978 .

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