What to do about it? I have 4 barrels chambered currently and all of them lead up. All of them lead up just behind the crown as Keith spoke of and 2 of them lead up the entire length of them in spots. One of them has inclusion holes in three spots in it. All of em shoot pretty well when they are lead free. 50 rounds wlll lay the lead back into them. One is a Shilen Ratchet that, because of a big tool mark at two inches behind the crown, is an iffy performer. Interestingly though, it does not lead up there. It does lead up badly where the choke gets tight, as do the others.
If one does not have a bore scope, they can not know they have lead. Patch color will tell one if they have lead but it takes experiencing the removal of lead, only after the other fouling is removed, to know what it looks like.
From my experience, rifles never shoot better than they do after fouling shots from a spotlessly clean barrel ( meaning NO wax or anything else). Two of my barrels are on their 6th or 7th season and been shot a lot. Both of em will still win matches when I can get my head into the conditions. Now, I think the age and wear on them has made them less forgiving to conditions but they still shoot very well most of the time. I have done all and more of the don't doos to keep them clean. Both the old ones have no lands or groves in the bottom of them and one has to look closely to see any chamber beginning at their breech. They still shoot though.
I have been chasing the lead removal thing for quite some time and have found a safe method that works. Rather than to be ridiculed by those who have never experienced a leading problem, I won't get into here it but if anyone is interested, PM me and I will share it.
Pete