The bores of my Model 1883, shipped to Wm. Read & Sons, Boston, MA, February 4, 1892, measure .734" right and .733" left with .029" choke in both barrels. My gun has a flat rib which is mentioned in the letter from Colt, while I see Bruce's gun has a concave (hollow) rib. My gun has 30-inch barrels and weighs in at 7 pounds 7.2 ounces.
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