For the record I don't think it is a manufacturing issue. (Could be but evidence is not that strong - sorry Tony but I need to say it and I am sure you will forgive me eventually) Please everyone be careful of blaming manufacturers until all investigations are carried out. I do however believe the manufacturer will be the best help here. They will let Tony know if there indeed has been any other issues and replace his barrels for sure if there was. If not then you need to look closer to home.
1) Only two barrels so far found with this issue. Both with the same owner. Until more are found there is a stronger correlation with owner than manufacturer (2/4 barrels compared to 2 out of thousands). If Tony had only 1 then I would suggest it could just be a Dud but 2/2 from that time whilst other owners have no issues is a bit strong. It could be but we need to find more before jumping to conclusions. Perhaps if all those with borescopes and Bartlein barrels can take a look. I have looked down a couple up here in the recent past and seen nothing like that. I have also just asked a couple of people I met in the states that use Bartleins and they have never heard of this issue either.
2) The direction of the grooves tells me it is not a soft steel issue. If it was soft steel "peeling" or other then it would be in the direction of the rifling. This is not. It also does not appear to be stress fractures but true "gouges". Fire or stress cracking or peeling would be parallel or at 90 degrees to rifling. This gouging is more in direction of barrel, not rifling. It is working at odds to projectile and cleaning brush and patch direction.
So it appears to be something travelling fairly straight down the barrel. If it was done in manufacturing then I would have thought it would be noticed earlier than now and probably in their QA checks. Also Firing and cleaning projectiles would be smoothing rather than enhancing the gouges in this case.
It is so unique though that I don't like guessing but would look closely at all processes that go straight down the barrel not with rifling (manufacturing, cleaning and firing etc). Brads joking suggestion of garnet in the powder sounds crazy but actually makes some sense???????? or those stupid ball bearings used for lubricating necks that find there way into the powder. The gouges look consistent (machine like) in one photo but quite random in others.
Sorry Tony but I see a great deal of frustration ahead for you. If one still shoots well then bench the worst and fire the better one and closely watch what is happening as you proceed.
I feel for you.
VERY VERY PERPLEXING!?????