That is not inconsistant with Josh's declaration that the round it fires would not be considered a full sized battle round. That would also move us closer to realizing which caliber is the red-haired step-child. Candidates remaining: .50MG, .45-70, 12.7mm, 5mm, BB & .44 magnum.
Nope, we know there's a .44 Mag Revolver. Josh has mentioned it before, I believe.
I'm starting to think it's actually the BB, because unless there's a BB pistol as well, what else would fire it?
Also, I think http://www.gamesas.com/index.php?/topic/1112926-weapons-mods-and-ammo-mega-thread/page__view__findpost__p__16327240 post suggests there will be an 1886 lever action in .45-70.