Trapdoor chamberings

[Fogman01]

A guy I know has a Springfield trapdoor rifle he just bought. He was told it was a 45-70 like most are. The gunsmith chamber cast it and it looks a lot like a 43 Spanish. It definitively has a bottle neck - not straight. I have some 43 Spanish cases and I'll see if they will fit. I'll remeasure the bore too. The guy said it was .43 something. The cases are from a rolling block and I know the rollers were chambered in about anything since they were made for a lot of different foreign military contracts. Is that true of trapdoors? I know very little about them. What were they chambered in besides 45-70? This one is marked in the 1880's not sure which year and he said it does not have foreign proofs on it. We won't shoot it until we are sure what it is.