I have never used Bore Butter and really haven't heard of many inline shooters that do. I had a tube given to me and thought about throwing it away or giving it to someone. I scrubbed the Encore using a hot water dish washing soap mix then I used three different gun care products until the patches were clean coming out. For whatever reason (bored or obscessive compulsive disorder) I tried running a patch with Bore Butter on it through the barrel. It was completely black! I've probably run at least eight others through the bore and they have all been black. I'm finally starting to get lightly soiled patches to come out, this stuff appears to be incredible at removing fouling I wasn't even aware existed. Any comments regarding Bore Butter or my cleaning session appreciated, I have no experience with this stuff nor do I know any of the negatives involved with using it.