There was a change to the handheld AT weapons in july 2009, which set the damage to 55 for bazooka, panzerfaust 30, panzerschreck and piat, as a part of a whole new tank damage model.
I feel too like this is too simple and we should try some adjustments there to reflect the differences of those weapons more, but of course these settings are in use since some time now, changes there might lead to other imbalances and even more problems than a weak panzerfaust 30m. But as long as we adjust between 55 and 90, it should be ok I guess, especially the one shot panzerfaust should not be weakened.