A barrel I used for a couple of years went off on me telling me it wanted cleaning, pulled it through which I usually did every couple of weeks but it didn't come back, tried again and it was still not as it should be. So I put a few drops of carb cleaner down it and gave it a scrub with a nylon brush then pulled it through again, the muck that came out was quite surprising! and the barrel did return to being accurate. So there was something in there even a really tight pull through would not shift. I had to do that twice with that barrel during its term of office.
So if had a barrel that was not as accurate as I knew it could be after a normal clean it would get that treatment.
HFT, for people with only 2 buttucks!
VooDoo TwoTwo The next chapter.