You may find this site helpful . . . .
https://armscollectors.com/trapdoor/
Lots of great info here!
[COMMENT FROM MODERATOR:
The link is to the main Trapdoor Collector site, which is the main entry point to this forum. There is indeed LOTS OF GOOD STUFF THERE! Almost all of it created by Dr. Albert Frasca, founder of the site, and author of the two definitive books on Trapdoor Springfield rifles. We are all indebted to him for his many years of superb research and writing, and sharing his vast knowledge. John S.]
In addition . . . .
Moderator: 45govt