I've have done that as well and still have the same issue. I even changed the key bind to another key and to the 3rd mouse wheel button. Still no snap zoom. I Still have mouse wheel zoom but it but zooms to x30 instantly with just one notch of the wheel and I have roll it back to see what the heck I'm shooting at. The bug fixes itself when I update mod pack, but soon as newer version comes out. It does the same thing. It didn't start doing this until about 5 to 10 updates later before Tank 1.0 about ver. 0.9.15 ish