Your serial number indicates that your Springfield trapdoor model rifle was made in the year 1887.
about 1886
There are no model 1878s. You have a model 1873. Check out www.trapdoorcollector.com for more info.
Your trapdoor was made in 1884.
According to this proofhouse website http://proofhouse.com/colt/index.html the model 1878 was only made up to 1905 with the final serial number being 51210. I don't know how much your gun is worth but with a serial number 117187 it is not a model 1878
The Colt 1878 frontier model with serial # 35369 was produced around 1896.
made about 1881
the trapdoor model...................
made in 1887. caliber 45/70. vlue depends on overall condition. anywhere from $300 - $900 +
If this is the Colt 1878 Frontier model serial # 5100 , then it was produced around 1881.
value depends on the pistol model, overall condition and serial number. If a good early model single action, value could be $1500 - 2500..............................................
I am the one asking the question about the springfield us model 1878 and it's value. I have (2) in very good shape that i acquired a while back and would know the fair market value so when i decide to trade or sell them i can be on an even playing field. you van e-mail me at ira003@centurytel.net thank you.