Anyone have a clue on what rifle this is and the caliber? I cant find it anywhere. It has some crown proofmarks with a F, B and another with N under it and the year 1874 and a bunch of numbers with an 195K on top of the front ring but thats about all the markings. And the bolt is HUGE and it has a real high ladder sight. Its actualoy in pretty good shape for the year it was made plus the bore is pretty clean with a few minor pits that looks like their from using BP cartridges.