Hi Two Flints,
I recently purchased a Spencer carbine, SN 47922, in 56-56 from Rock Island Auction.
Two Flints attached the several photos. This carbine is, remarkably, a centerfire 56-56 with 6-groove rifling. Rock Island, in the gun's description, (or in the additional information I requested) did not indicated that it had been converted. So, it was advertised as a mid-grade Spencer and I paid a reasonable price. Very pleased when I opened the package and saw the firing pin.
Interestingly, the top block is solid, drilled thru for a firing pin, so not an S and S type conversion. It must have seen civilian service after the Civil War, cause the owner inlet an escutcheon plate, but if anything was inscribed on it, it is not readable now. The firing pin strikes low on the primer, but fires reliably. I don't know that it would also fire a rimfire cartridge, but my bet is that it would. I am shooting hollow-base bullets molded from a Lyman 533476 mold, with brass from 32 gauge shotshells cut to 0.9 inches, and it shoots reliably.
Also, this Spencer looks to have seen recent care. As received from Rock Island, all of the screws rotated easily and were lubricated. I asked Rock Island if they would contact the former owned on my behalf, and and see if he/she would open a channel for conversation, but they said that was against policy for privacy reasons.
So if anyone in the Society knows about centerfire conversions, or any information about its former owner, I would like to learn as much as possible.
Thanks,
Montezuma Johnny
SASS 100661
Photos Posted by Two Flints