50 cal trapdoor / 1873??

[Brad]

Friend dropped by here today with a Trapdoor that in every way I know looks like an 1873. The block says 73 and the lock says 73. It has the early sight also.
But then he tells me it is a 50-70?
I use my approx. muzzleloading "V" gauge and it is a 50 cal. Look at the chamber, definitly larger than the 47.
So I put a 50-70 round in it and it fits. BUT the trap will not quite close. Almost but not quite, won't click as when empty.
The barrel has the Springfield markings, everything?

I am not familiar with this model? Just curious about what it is. Could someone fill me in or tell me where I could read about this?
Thanks

[Dick Hosmer]

Itsabubba!

[Brad]

where would they get a barrel in a 50 cal that looks so correct? Proog mks, sights, ?? Unless some how they reamed the bore?? And the chamber?
But, it does look like a bubba!!
Thanks, hope ya been well Mr. Hosmer.
I havn't corresponded with you in some time.
Brad Foust

[Dick Hosmer]

A M1870 .50 cal barrel will, I believe, thread right into an 1873 receiver. Marks can be altered.

[Brad]

Thank you