It is deceptively difficult to see small changes which happen over a period of time - which is how accuracy usually detiorates - especially when shooting gong-type targets like many of us do. Even targets get us to believing we're losing it, or having a 'bad streak', when the problem might be mechanical.
The 'slick' shooting has been happening to Roger for a long time - this is the 3rd such thread he's stated on this subject with THAT barrel.
I'd not JB it as that is simply more and a finer polish, Roger. Even Flitz, which is more aggressive than JB compound, is still a fine polish.
Perhaps it's time to retire the barrel, "but it's such a good shooting barrel" - well, in that case, Dan's suggestion with the 120 grit is a good one- perhaps even 100 or 80 grit would be better yet, longer lasting. If the scratches run lengthwise, the accuracy should not be harmed in the least.
Oh yeah - wooden rods created less wear in my tests, than any other material. I neglected to try carbon, but I suspect it will be almost as bad as fiberglass. All materials tested were unprotected, of course. Testing a coated rod is merely testing the coating, not what the rod is made of.
I'd simply use more powder oh yeah- already said that.