Thread: What causes this

A VLD chamfer tool cuts a 22 degree internal chamfer on your brass to allow less deformation of VLD projectiles when seating them, it achieves its goal by allowing more precise lead in and less effort required to start the seating procedure.

The standard 45 degree cutter is mostly obsolete these days.

Another look at your brass and my guess is there is too much seating friction, either its dirty inside the neck/neck tension is too high/wrong lube.