You shouldn't have to file a PGC barrel to get a TM hop chamber to fit. You have to kinda massage it in there. Push it to the side and tap it in. Don't file anything you might ruin the way the inner and outer barrels interact.
here's a youtube video of lazouche removing and installing a metal 1911 outer barrel, the barrel assemblies are different but the ideas are the same:
LaZouche Custom airsoft how to fit metal outer barrels. - YouTube