I was perusing a local pawn shop the other day and noticed this unique old rifle sitting amongst the older stuff. It turned out to be a Springfield Trapdoor. I have never heard of these things and was wondering if the Gurus here abouts could help me find some info. What caliber is it? What period and service was it intended for? And what are they worth? The action seemed intact and fully functional but a little loose. It looked to be carbine length. Is this the right configuration? It was a really cool old gun but is it worth the $500 price tag? I don't think the wife would go along with my purchasing it but I know where it is if anyone else is interested.