I don't collect, but a bit familiar. Pictures would definitely help. Cartouche may be very hard to see... or worn off. But if it is a Springfield, there should be one somewhere.
Great shooters, but don't use 'modern' loads. When I say "modern" loads, I mean smokeless rounds that are designed for either Marlin or Winchester or Browning or Harrington and Richardson rifles that are modern and made for these modern rifles. These are available off the shelf from Rem/Win and maybe Fed.
That said, there are modern loads specifically made for Springfield Trapdoors and other BP cartridge rifles. Trapdoors are OK with smokeless powders IF very specific loading rules are followed. There are some good online sites or the old Speer reloading manuals specifically list some smokeless loads to replicate the original .45/70 BP loads. For those that don't know, .45/70 stood for .45 Caliber and 70 Grains of Black Powder. It was not a Smokeless powder rifle... but can use smokeless if loaded right and to specific guidelines. I have some loads if you need me to look up.
BP Cartridge shooting has gotten very popular. I have a Sharps BP Cartridge rifle that I love. Nothing wrong with loading BP cartridges for this rifle, but your cleaning regimen is much more rigorous. You will need to clean IMMEDIATELY after shooting if you load up some BP or Pyrodex (substitute) loads.
Again, Pictures, Pictures, Pictures. As much because I love looking at TD Springfields as anything. But this will be helpful. It's almost impossible to go wrong with one of these in good shooting condition. IMHO, I think they are very under-appreciated.
Cheers,
Sirhr
