Many long focal length lenses for LTM rangefinders use a tongue-like rangefinder cam that projects from the back of the lens. This hangs up on the body's focusing feeler on FED and Zorki cameras and maybe some others, preventing them from screwing in. Don't force it. On a Canon rangefinder, there is a little wheel or maybe a rounded shape on the body's feeler so that the tongue can pass over the feeler smoothly.
For the FED and Zorki rf bodies, the FSU made long focal length lenses have a focusing cam surface that goes all the way around the lens, like on the 50mm, so one doesn't have this problem.
You would probably also find that the different calibrations for FSU-era vs Leica/Japanese lenses are "close enough" for the 50mm lenses but result in focus offsets with the longer focal lengths.
