I have a dataset with about 10.000 points and their coordinates in Epsg 31467, EPSG 25832 and something called Lagestatus 320 (GK and ETRS89, tú i don‘t know correct proj4 definition). I use NTv2 and a local Grid file to transform to 25832 and this works fine!
But the way back to 31467 or Lagestatus 320 does not work. All coordinates are inf. I have no idea, what is wrong!
Do I need a different Grid file?