Full Length Sizing vs. Neck Sizing

Full length sizing dies such as the Lee Pacesetter Dies, return the entire spent cartridge to a degree that will chamber in any rifle for that caliber. Lee Dies size cases as minimally as possible while still ensuring proper chambering so that your brass is not "overworked" by the die. It is necessary to lubricate the case prior to full length sizing.

We recommend full length sizing when shooting fired brass for the first time in any rifle. It is also the preferred technique for rifles intended to be used for hunting so that rough handling of the ammunition through the magazine and chambering does not become a factor for error.

Neck sizing with Lee's Collet Dies generally provides increased accuracy because the spent cartridge becomes "fire formed" to your specific chamber. No case lube is necessary because the die is only pressing the neck against the mandrel in the middle of the die. Neck sizing is only preferable when reloading cases that have been fired out of your rifle. They are primarily designed for accuracy when using a bolt action rifle for target use. Collet neck sizing results in cases lasting up to ten times longer without the need for trimming near as often, as when full length sizing.

The Dead Length Bullet Seater that comes with Lee's neck sizing dies is designed for accuracy and does not crimp the case as does the seater/crimper in our Pacesetter dies. It is designed to touch the shellholder to eliminate clearance in the press for a more uniform bullet seating depth. Crimping is seldom necessary for target work.

The Deluxe Rifle Die Set includes Lee's Neck Sizing kit along with a full length sizing die. This is because you may obtain brass that has not been fired in your rifle and it allows you to prepare the case for its first firing in your rifle. Remember, it is necessary to lubricate the case for the full length sizing die only. After your first firing only the collet sizing die is required.