Quote Originally Posted by lacavol View Post
The Russian lenses actually have a different pitch thread from the Leica lenses.
Never heard this one before.. Maybe the very early lens but not the post war screw mount Jupiters..

I have several Jupiter lens and never had an issue mounting them on a Leica..

Quote Originally Posted by lacavol View Post
Sometimes this is a problem as they don't screw down all the way without bunging up the threads.
Never had this proble either..