Need help deciding what to do next, having issues with a barrel. Cartridge is a 7/300 Win, H1000, 180 Berger Hybrid and VLD's @ 2900 to 3140 with an 8 twist. Top 3 barrel manufacturer I would say, cut rifled. First shot down the barrel had quite a lot of copper fouling, much more than any of my other custom barrels. Shot 1/clean for the first 10 rounds. Copper didn't seem to get much better or worse. Started shooting strings of 3 then clean, didn't really do any better or worse. Chamber goes from no pressure to pretty heavy bolt lift in about .4 grains and it's not consistent. Initially it pressured out at 3140, some days it can be as low as 3090, same elevation and temp. Called the manufacturer and told them the deal, they said to pull all the copper out and run some JB through it and see what it does. Took me about 2 days of morning, lunch and evening to get all the copper out with BT C3. Took about 15 strokes with JB in each 3rd of the barrel (what the rep I talked to suggested. Took a mild load (for cartridge) of H1000 and 180 VLD's and shot 1, 3006 fps. After 1 shot the bore was fouled terribly for the last 2/3rds. That's where I am at. Not sure where to go next. They said I could send it back, but it would take quite awhile to get it looked at and get a new one to me. Season is here and I'd like to get it going. First pic is after pulling all the copper out and running JB through it. 1 shot. Total of 87 down the barrel. Second is of a crack or imperfection in the throat, just where the rifling begins. Fairly sure this has at lease something to do with where the copper is coming from. Third is of some strange diagonal marks that start about 6 inches ahead of the throat and continue on each rifling down the bore. They do not really seem to be spaced incrementally, but more or less there are 2 of them about .2 inches apart and then show again about 3 inches down each rifling again. I have no idea what they are from, I can't imagine I did then when cleaning it. Used nothing but Boretech and JB with a bore guide, carbon rod, nylon brush and proper jag. Some are deeper than others, this is probably average. I would love to just shoot it and see what it does, but it is so inconsistent with pressure that I'm a little hesitant to. Any Ideas?