Hobbed bolt grinds in to filament

Hi everyone

my extruder has not been working for a few days now, since the hobbed bolt starts grinding into the filament after a few millimeters extruded.
A few weeks ago I installed a e3d v6 and also changed the filament, but I have made several nice prints before this happened.
I checked the hot-end, it looks clog free, and also everytime I insert the filament again after cutting off the grinded part, it works again for a few mm, so I guess it’S not the nozzle.

Anybody got an idea here?
Also where can I get a replacement hobbed bolt or a better one?
I have been searching and didnt find anything.
Only thing I found is this here: velleman.eu/products/view/?id=420498
But its only for 1,75mm filament. Is there also a version for 3mm filament?
Thanks in advance

Just grab your dremel and a thin cutting disc and grind the teeth a bit deeper, so the edges get shatper.
I did that for the same reason (E3D v6 needs more force) and it totally did the trick.

cheers,

Christian