I would hope Mule Deer will chime in on this subject, especially in relation to a rifle that has been properly cleaned down to bare steel and then Dyna Bore coated.
I believe he has stated in the past that while the company used to say no phosphor bronze bore brushes they then said it was ok, their dyna bore coating could withstand it???
Of course they have no customer service/support anymore so you can't find out from them.
And as stated above bore scope is the way to go in accurately judging how clean your barrel is.
A bronze brush won't hurt DBC, but it's not necessary in DBC'd barrels, either.
These days, about the only use I have for brushes of any sort is to prep a fouled barrel for DBC.
