What bullet are you using?I have about 400 rounds down a 30/28 nosler and the accuracy node has slowed down about 60 FPS. I use to run 3100 all day long. Suddenly she dropped off. When barrels slow down does this usually mean there close to being done?
Have you kept the depth the same? Or chased the lands (moved the bullet out) as they've worn down?The lands have moved .009 in 400 rounds. I check every hundred. I have kept seating depth the same. But larger bore diameter for a short distance would make sense.
I have tried to understand that. Someone else mentioned copper fouling. But I did recently clean it. If friction is increasing wouldn't it make the bullet and pressure faster. Like when a new barrel gets broken in and speeds up.