I have a selection of pre AI Nikkor lenses which I sometimes use on a D3200 (although I prefer them on a Nikon F). I also have a Helios 4 which I converted to Nikon mount. I have no problem focusing these.
Also, I recently found an adaptor which allows me to use an old 500mm lens which I inherited from my father on the D3200. It's a bit long with a cropped sensor though. It's more like a telescope!
Steve.