I have an original 7r and a 7r3. When I attach a non-Sony lens to the r3 it's so tight that it's hard to get it on. The same lens on the original r is just fine. I used to think it was my Metabones Canon to Sony adapter but I just got a CV 21 for E mount and it's exactly the same. I'm concerned about the constant pressure on the camera and lens mounts - I know that replacement camera mounts are available from people like Fotodiox but they are for a tighter fit because the original r mounts could be a bit sloppy. Anyone know of a way to loosen it up and still keep the alignment?