It appears that the boys and girls at Ilion didn't rush into updating the roll-stamps used on their shotguns. The Model 17 20-gauge pump was introduced in the first Remington Arms Co., Inc. catalog circa 1920/21. However, up through the 28xxx range the barrels are still marked The Remington Arms Union Metallic Cartridge Co., Inc. which was the company name 1916 to 1920. This from serial number 28023. Unfortunately, the first Model 17 page is missing from the old factory ledger. Page 2 begins with 35639 being the highest serial number receiver put in work by January 19, 1926.
28023 01 The Remington Arms Union Metallic Cartridge Co., Inc..jpg
The date code on this barrel is DR D = September R = 1924
I just noticed this Model 11 which came on GI yesterday. It is serial number 280017 a receiver that the old factory ledger shows was put in work during May 1924.
280017 02.jpg
This barrel has a date code WR W = August R = 1924 --
280017 03 WK W = August R = 1924.jpg
They seem to have taken a bit different tack with the Model 10 pumps --
207380 01 Model-10 Successor To.jpg
215875 01 30-inch, solid rib.jpg