I'd wear safety glasses for sure!
Really though, the others have 11/16-24 for that reason. Pressure wise the chamber takes most of the pressure so if it's just the tip that's slightly thin, you are probably more at risk of ripping the threads out due to bumping the suppressor. The suppressor insert will also reinforce the threaded area, IE it will only expand slightly until the thread clearance is taken away. If it cracks, it will crack at the transition of the barrel to threads where it should be undercut. The undercut is so the suppressor sits against a flush surface and not fully dependent on the threads for alignment.
I am also not a barrel threading expert, so if you hurt yourself or others, this is the disclaimer I will use so you don't sue me.