I have a Chiappa Spencer carbine in 56-50. Beautiful little gun! Gorgeous case colours in the receiver and hammer. Great looking wood. Good little shooter at 50 yds.
Did I have issues with it? Yes. The barrel band was loose and after about 20 rds, the barrel seemed loose! As a long time resident of CasCity, I appealed to the 'sperts on Spencers and was buried in information. They even have a FAQ forum on trouble shooting them.
The cure for the barrel band was to put a strip of electrical tape inside of the barrel band. Done.
I emailed Chiappa in Italy and was told to LocTite the barrel in place! I did and no problems since. That or contact Grech Outdoors. A quick check on reviews of Grech and that was not an option.
I was gifted with a copy of Marcot's book on the Spencer, an out of print volume that is the Bible on historic Spencers. Goes for $200 USD if you can find one.
You have to operate the Spencer as if you were mad at it. If you baby it, it will not feed reliably.
In the Marcot book there is a comment by a US Army Officer that he ordered his troops to discard the mag tube, load 5 instead of 7 rds, plug the butt with a rubber or wooden plug and to point the gun at the ground when operating the lever, letting gravity do the work. He was right!
You also do some grinding polishing on the breechblock in a critical area, but I chose not to do that. Done incorrectly, you only create new problems.
You have to remember that it is 1860s technology. DO NOT drop your rds vertically into the gun, especially if you use Federal primers! Just like the Henry, it is asking for trouble.