Made between July - September 1889
Quarter production started w/ S/N 450282; ended w/ S/N 459533
"SWP" in the cartouche block indicates that Samuel W. Porter inspected the rifle in 1889. Porter was the Springfield Armory Master Armorer & chief inspector from 9/15/1879 - 6/18/1894.
Source:
Ernst & Waite, "The Trapdoor Springfield; the United States Springfield Sing-Shot Rifle, 1865-1893"
Bienfeld Publications, 1980
ISBN 0-917714-20-2
On line purchase thru Buffalo Arms:
http://www.buffaloarms.com/browse.cfm/4,3222.htmAlso "Loading cartridges fro the Original .45-70 Springfield Rifle and Carbine"
www.the45-70book.com/B3/books_Reloading_Collectors_Info_Third_Edition.htmlSome Tradoor sites:
http://www.trapdoorcollector.com/http://www.trapdoors.com/Log onto the below site & type in the complete serial number. It may give you some additional history on the firearm.
http://www.armscollectors.com/srs.htmBe advised the information given is for
individual serial numbers only! If your rifle S/N falls between 2 serial numbers that say were issued to Indian Wars or Spanish American War units, don’t assume that your rifle saw such service. Again, the information provided is for
individual rifles only!