Hello, Glenn:
I chased that sort of info during my May, 2018 Taylor's visit on behalf of another Armisport Spencer original owner having an oddball mixture of 45LC parts in a 56-50 receiver.
I have an opinion about how the carbine got that way:
My opinion is based upon 45LC parts being discovered in his "56-50", and the sequence of conversations about the gun.
The buyer called the distributor because no dealers had a 56-50 in stock.
Buyer made it clear that because of an important personal aspect it had to BE a 56-50.
Buyer then was told that "there were no 56-50's in stock".
Buyer passed on the alternative of a 45LC version, emphasizing that only a 56-50 would do.
Soon afterwards distributor indicated: "We looked more and found one."
The only thing that makes sense to me is that a 45LC version with its 45LC barrel was merely rebarreled into a 56-50, but he other internals for a 45LC gun were left in place!
Part of the cycling/feeding issue was later traced to a CLEARLY and VISIBLY different cartridge feed guide than one for a 56-50! I have photo's and dimensional drawings of both cartridge feed guides. Winchester, after seeing them, cheerfully provided a free 56-50 ctg feed guide that PARTIALLY helped cycling, but did not clear all issues, including bullet nose catching at times and block over rotation.
Recent private sharing by a different SSS member points to another of these 56-50 barreled odd-balls out there!
My hunch is that Chiappa, Dayton "would/should" know about distributor performed caliber "conversions.
The Winchester Taylor's people were extremely nice to me. Ryan Hodges said that because "Winchester" deals only with the latest production, all other records for older models, earlier serial numbers, production dates and production VARIATIONS to match parts to serial numbers are available only from the Chiappa Facility in Dayton, OH.
Ryan Hodges was at 540-722-2017 ext 114, in May, 2018. He was super professional.
I think that he quickly sensed WHY I was inquiring, gave me his card and wrote on its back to call Chiappa, Dayton and ASK for "TJ".
I do not know if the owner of that "oddball" one inquired of Dayton about serial numbers, etc.
Because that gun has a private sentimental aspect, for now, he'd rather hang it on the wall than have it replaced.
His son's Armisport 56-50 Spencer cycles fine and when ITS block and other 56-50 internals are put into the BALKY ONE, it cycles better.
Thanks for all your sharing.
Regards,
Kevin