Bushing Dies?

Over the last 36 years I have loaded many thousand rounds of handgun ammo, and bunches of rifle ammo. However I have never used a bushing die set. Can anyone explain to be what a bushing die is and how it is used. What are the advantages of such a die?
Thanks in advance.

 

A bushing die uses a bushing to size the case neck. There are neck bushing dies and fl sizing dies with neck bushings. The bushings are chosen by size. Usually you measure the diameter of a loaded round at the neck and deduct something like .001 or .002. There are lots of opinions about bushing dies and how well they work. Personally, I don't recommend them for factory chambers or unturned case necks. Others feel differently.

 

Standard dies may size the neck a lot smaller than needed. Then the expander opens it back up. This over works the brass, work hardening it, causing the neck to crack soomer. Less case life. Sizing only 1/2 of the 243 win. neck, centers the round in the chamber, producing better accuracy. If neck has to be size down more than .008" there can be problems. [/URL][/IMG]Others feel differently. [/URL][/IMG] I use the same die for a Rem. Mohawk 600.