I got a new shilen 308 barrel recently, it has a 340 neck and custom throated. Ive got about 200 rss through it and am not impressed. It is probably a 1moa barrel at 100 yds.

I think something was machined improperly in the chambering/ throating. When I use my hornady oal gauge to determine distance to the lands I come up about 0.1" shorter than the dummy rounds. If I tap the gauge with light to moderate force the bullet seats deeper and "hits a brick wall". This measurement is exactly identical to the dummy rounds I sent shilen. I marked a bullet with a sharpie and do this again, when the bullet first stops I take it out and only get marks on 1/4 of the bullet. If I continue and force the bullet until it stops I get marks all the way around it, like I would expect.

Initially I thought this was a bur and shooting it would erode it, but after 200 rds of poor accuracy and no change I'm thinking some thing was cut off axis to the bore

What else could it be???

My loads have been lapua brass 168 SMK and 175 SMK with varget powder ranging from lite to near max, length identical to dummy rounds and 30 thous short of dummy rounds.

Please help