I doubt many, if any, 20-gauge Sterlingworths left North 18th Street and Windrim Avenue chambered for anything but 2 1/2 inch shells. Some graded guns were ordered with longer chambers. Two I know of were both 30-inch barrel, straight grip and weighed right around 6 pounds, 200108 DE-Grade and 200109 CE-Grade. In that 1913 time frame, Parker Bros. made the famous "Widgeon Duck Club" 20-gauges chambered for 3-inch shells, and the J. Stevens Arms & Tool Co. brought out their No. 200 pump gun made for 3-inch 20-gauge shells. In those days, most of the benefit of the 3-inch 20-gauge shells, or any gauge longer shells, was more and better wadding. The max load for the 2 1/2 inch 20-gauge was 2 1/4 drams equiv. of dense smokeless powder pushing 7/8 ounce of shot. The factory 3-inch 20-gauge shells of those days carried 2 1/2 drams equiv. pushing 7/8 ounce of shot, or the same as a Skeet Load today.
With the A.H. Fox Gun Co. policy of holding chambers 1/8 inch shorter then the intended shell, a factory original Fox 3-inch chamber would measure 2 7/8 inch.
