Re: bullet seating problem
One thought - If your die is set too low it will crimp the mouth, often well before the bullet is fully seated. I keep the die backed out so it does not crimp at all. Run an empty case up into the die and measure across the case mouth to make sure it's not too low and crimping, or run the ram up with the die backed way out then screw it down carefully until you feel resistance from the taper inside the die contacting the case mouth.
You probably have not chamfered the inside of the case mouths if they are "entering" the mouth really rough?