Some older Nikkors, in particular wide-angle lenses, have a dominant protruding shroud in their stray light baffle that can cause issues with modern cameras. One notes the problem for example when attaching these lenses to an FT-1 adapter, or an FX camera. The solution is easy, just remove about 1 mm of the flange and the issue is gone. I have a jig comprised of one-half D3X body, the frontal part, that allows me to find any misalignments or problem-causing fit before trying the lens on a real camera.
I have seen oversized baffles on early 20/3.5, 24/2, 28/3.5, and 35/2 to name some. These lenses will fit most, but not all, Nikons.
The "bump" in the lens when the shutter is released could be caused by the return spring of the aperture lever not being taut enough.