Age of J Stevens Arms 20 gauge shotgun?

It had to be after the patent date of 1912 and the "and tool" part of the name was not used after 1916.

The Stevens No. 200, 20 gauge pump shotgun was the first 20 gauge pump shotgun. It was the brainchild of the famous trapshooter, Charles (Sparrow) Young. Sparrow Young is in the trapshooting hall of fame and was the first shooter to break 100 straight from back yardage. In 1910 he patented the original idea which became the No. 200. Sometime in 1912, George Lewis, one of the higher-ups in Stevens, also filed patents on developments of Mr. Youngs gun that was already being manufactured as the Stevens No. 200. The No. 200 was a hammerless pump 20 gauge which could handle 2 1/2", 2 3/4" or 3" shells at a time when most 20 gauge shotguns were single shot "boy's" guns which could only handle the 2 1/2 inch shell. The Stevens No. 200 was only made from about 1911 to 1914. It only appeared in one Stevens catalog. Based on serial numbers, there were only about 20,000 made. The highest serial number observed is in the 19,8xx range. The Stevens No. 200 operates with a very short bolt which is held in place by a tilting "carrier". It also has two blades which, when the pump is acuated, first keep the shell from rolling out of the partially closed action, and second, seal the hole behind the very short bolt. In all, a very complicated gun. It is a takedown shotgun. There is a special spanner wrench in the end of the magazine tube which can be used to turn an interrupted screw which holds the barrel onto the breech. There is a tang mounted safety like on better grade double barrel shotguns. It weighs from 5 3/4 to 6 1/2 pounds, depending for the barrel length. All barrels are choked "Full" unless the barrel is marked otherwise. The gun was meant to be a combination of a light "field" type gun for upland game with a heavy duck gun (when firing the 3" shells. But, I have been told that before WWI, 20 gauge 3 inch shells could only be bought special order and by the case and that, even then, they really didn't have a heavier charge of shot or powder than the 2 3/4 inch shells. I really like the No. 200.

On serial number 1712x, the Patent dates on the shotgun are marqued as: Apr. 12 - 10 and Apr. 2 - 12. It was not simple to take apart and assemble indeed, 30 inch barrel and 5 shots. I found it a pleasure to hunt with.

my guns serial # is 19197 with same markings i might sell for parts if interested email me