I have seated 87 gr. HPBT bullets in 6mm - 06 cases necked down from 25-06 cases to fire form to 6mm - 06 Imp. The bullets seated fine in the cases to be fire formed and they fire formed beautifully. I then neck sized (actually partial sized with the FL 6mm - 06 Imp. die) and attempted to seat the same brand 87 gr. HPBT bullet. I have been unable to seat the bullet into the fire-formed cases without the shoulder collapsing; the neck is being pushed down into the shoulder. I have lubed the bullet before seating and that didn�t help. I have ruined several cases and decided to ask for help with this problem.
Any ideas?
Thanks,
Don
