My fully optioned No. 4E 20-gauge with 30-inch barrels has no choke markings. They measure .038" and .042" which is a lot for a 20-gauge. Over the years I've recorded half a dozen or so long barrel, fully optioned, 20-gauge NIDs, most in the 457xxx serial number range, several with no choke markings. A 32-inch No. 7E 20-gauge that Julias sold some years ago --
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A 32-inch No. 5E 20-gauge --
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