Welcome to the world of Ansley H. Fox shotguns. I'll post my canned Sterlingworth response for you --
Sterlingworth -- When Ansley H. Fox, was forced to add a lower priced gun to his line of graded Ansley H. Fox guns, in 1910, he didn't want to detract from the A.H. Fox Gun Co. name, so they dummied up "The Sterlingworth Company." The first year’s guns, beginning with serial number 50,000, were marked as being "Made By The Sterlingworth Company, Philadelphia, U.S.A." Actually the first few hundred were marked "Wayne Junction" instead of Philadelphia. They even produced a separate The Sterlingworth Gun Co. catalogue for 1910. These guns were built under the same patents as the graded Ansley H. Fox guns. The main moneysaving features were an American Black Walnut (Juglans nigra) stock as opposed to the more costly European thin shell walnut (Juglans regia) stocks on the graded guns, and the "Sterlingworth Fluid Steel" barrels instead of Krupp Fluid Steel barrels. Workmanship on these early Sterlingworths was generally excellent, better than graded guns from the 1920's and 30's. The early "The Sterlingworth Company" guns had a rounded front for the side panel of the frames. According to my list of observed specimens that was changed to the same pointed profile as the graded guns by #51,301.
In 1911 this field grade gun was added to the A.H. Fox Gun Co. catalogue as the Model 1911. "Model 1911" is stamped in the forearm iron. (A very few graded guns made about this time are stamped Model 1910) The lowest Model 1911 serial number I've recorded is #53,140. All of these early Sterlingworths had a recessed hinge-pin head like Parkers, or Ansley's earlier guns made in Baltimore and the Philadelphia Arms Company A.H. Fox gun. The highest "pin gun" Sterlingworth serial number I've recorded is # 62,244. After that Sterlingworth hinge-pins are dressed smooth like the graded guns. When the small-bores (16- and 20-gauge) were added to the Ansley H. Fox line they were briefly referred to in some flyers as the Model 1912, but I've never seen one so stamped. Graded 20-gauge guns have serial numbers beginning with 200,000 and 20-gauge Sterlingworths 250,000. Graded 16-gauge guns have serial numbers beginning with 300,000 and 16-gauge Sterlingworths 350,000.
Most of the Philadelphia produced S-worths had the word "Sterlingworth" roll stamped on each side of the frame. After production moved to Utica, Savage started using a "Fox-Sterlingworth" roll stamp.
When the Sterlingworth came out in 1910 it had a price of $25. The price stayed at $25 thru 1916, then climbed quickly to $55 by 1919. A.H. Fox Gun Co. reduced the price to $48 in 1922 and again to $36.50 in 1926. Workmanship of course declined.
Parker Bros. introduced their Trojan Grade at $27.50 in 1912. The Trojan’s price climbed like the Sterlingworth to $55. Parker Bros. kept the price and the quality of the Trojan high and sold about 33000 total. Fox began cutting the price of the Sterlingworth and sold well over 100000.
Savage kept the $36.50 price until June 1932 when they upped it to $39.50. On February 10, 1936, they upped the price again to $42.85 (the digits 2 and 8 are transposed in McIntosh's book). On February 1, 1938, Savage tried a price cut and dropped it to $35. February 1, 1939, they upped the price to $44.75. January 2, 1940, up again to $48.50. January 2, 1941, up to $52.65 and June 16 up again to $56.50. January 2, 1942, up again to $64.95.
For $40 Graded or $30 Sterlingworth (last prices I've seen quoted) you can get a factory letter on most any Ansley H. Fox shotgun (Philadelphia or Utica) from Mr. John T. Callahan, 53 Old Quarry Road, Westfield, MA 01085. The information exists on the factory work-order cards, probably 85+% of which still exist. Send him the complete serial number and a check, and he can do the rest. That would tell you the specifications of the gun when it left the factory.
There were more 12-gauge Sterlingworths made than any other Fox double (some 110,000, the great majority with 30- or 28-inch barrels), so unless in exceptionally high condition or with features such as automatic ejectors or factory original 26- or 32-inch barrels, they are about an $800 gun. It is impossible to truly evaluate a gun with out having it in hand, but average 12-gauge Sterlingworths are about $800 guns.
To Phily or Utica, That Is The Question – As with all American doubles earlier the Ansley H. Fox gun the better the workmanship, and quality of wood grade for grade. I have seen some pretty lame very late Utica Fox-Sterlingworths. I haven’t observed that much of a decline in the quality of the graded Ansley H. Fox guns built by Savage. They seem to remain pretty much the same as the late 1920s Philadelphia built guns, except for the uglier profile of some of the top-levers, and the bulkier forearm wood, which some like and some don’t.
The older guns often have more drop at heel than most people like today. The standard drop-at-heel for Philadelphia vintage Sterlingworths was 3-inches for 26-inch (Brush) and 28-inch (Field) barreled guns, and 2 3/4 - inch for 30-inch (Standard) and 32-inch (Trap). Names in () how factory referred to various barrel length Sterlingworths. Stock dimensions were to order on graded guns so anything is possible. I have a 1914 A-grade 12-gauge straight-grip that came from the factory with 2 1/4 inch drop-at-heel. A friend has an AE-grade 20-gauge with 3 1/2 - inch drop-at-heel! All the Savage vintage catalogues list 2 3/4 inch drop-at-heel as standard for all barrel length Sterlingworths. Later guns also tend to have their barrels a little less finely struck and hence weigh a bit more. While the Sterlingworth was always stocked with American Black Walnut (Juglans nigra), pre WW-I graded guns were all stocked in European Walnut (Juglans regia). After WW-I only XE-grade and above were listed in the catalogues with Juglans regia, and by the last Savage catalogue all mention of European Walnut had disappeared.
From your pictureds, it appears someone buffed the reciever bright. Sterlingworths all started life with color case hardened receivers.
A good part of assessing the condition of the old "classic" American doubles is the percent of the original case colors remaining on the receiver.
In the 30 years I lived in the Old Dominion, I shot lots of Doves with various Sterlingworths from my collection, and I still shoot a lot of Skeet with my Fox-Sterlingworth Skeet & Upland Game Gun.
Dave