Coldfinger wrote:Aromatic hydrocarbons such as xylene or toluene are the best solvents for polyethylene. Chlorinated solvents like trichlorobenzene or trichloroethane will also work. All work better when hot.
Not sure I agree I'm afraid .. I had the same problem with my Benelli supernova which spent much of its early life shooting plastic wads ... I was of the same view as you initially, and tried everything and eventually went to wash with Xylene which had totally no effect
... Ive just Bought a new Beretta A400 Multitarget .. its had 150 fibre wad shells through it and looks just as bad after some 009 and a good bronze scrub as my Benelli did ? .. I know as others have said its not vastly important, but it kind of is IMHO... you shouldnt surely have a deposit that cannot be removed in there ? But I dont know what could possibly remove it ?