For the past 45 years, I've used .348 cases in all of my original 1876 Winchesters in .45-75 caliber. I have never had a problem with ejecting the empty cases and they look fine when extracted from an original chamber. Maybe the new repops have a chamber that is a little larger than the original. I've never had any experience with the Chaparral or Uberti, so I don't know. I also use .348 to make brass for my .50-95's and there is a slight bulge near the bottom of the case on this caliber. However, the brass is as tough as it gets and I've never lost a single case, so the bulge doesn't make any difference to me. If it were hard on the gun, then I would be concerned, but it has no effect, what so ever.
Adios,
Buck.