Most "consumer grade" swaging dies fall into a few basic types, designed for a specific task in the overall process:
De-rimming dies, jacket making dies, trim dies, 'base guard' dies, and similar tools are not really 'swaging' dies; but used for making components to go into bullet swaging, or are niche products. So, I won't cover those.
Lead swage die (known by many other names) - These dies are designed to form bullets from lead alloys, without jackets. They can use nearly any form of solid lead as the core (due to the use of lubricant in the process, multi-segment bullets are not recommended). Most bullets formed by these dies must be cannelured, knurled, or grooved, in order to be lubricated -- exceptions made for some applications, such as black powder and paper-patching.
Core swage die (aka "Squirt die") - This die is used to squeeze pieces of lead alloy (wire, cast bullets, or cast cylinders) into a uniform cylindrical shape, with excess lead being bled off through vent holes. The extruded waste is collected and recycled. The finished cores are extremely uniform, and ready to get swaged into jackets; or used for swaging lead bullets in the dies mentioned above.
Core seat die - This die is used to seat the lead core in the jacket of choice, and expand the bullet to very near its finished diameter. Generally, the "bullet" comes out as a cylindrical hollow point.
Point form die (aka "Form die") - This die is used to form the ogive of the bullet, and uses the pressure created during the process to 'bump' the bullet up to its finished diameter. Most hollow point and flat point bullets are finished after this step (other than being washed or tumbled clean).
Lead tip die (aka "Pointing die") - This die is used to form a more attractive point on bullets that have exposed lead on the bullet tip. It is mostly cosmetic, for rifle bullets, with some minor impact on ballistic coefficient and/or feeding reliability. Most pointed bullets are finished after this step.
One-Step die - This die is used to form a completed handgun bullet, in a single press stroke (provided your cores are uniform, or you don't care about minor variances). Generally, 'one-step' dies only create a hollow point, due to the need for applying pressure to the core during the process. Most 'one-step' dies are designed to use some type of handgun cartridge case as the jacket - .40 S&W for .44/.45 caliber bullets, 9mm for .40 caliber bullets, etc.
Most swaging dies for swaging presses have the die mounted in the bottom of the press (whether it moves, or not), and the punch mounted in the top of the press. However, most swaging dies for reloading presses operate in the opposite manner - die on top, punch on bottom.
"Such is the strange way that man works -- first he virtually destroys a species and then does everything in his power to restore it."
Last edited by FrankenMauser; January 19, 2013 at 03:14 AM.