There are three ways to make bullets:

1. Casting is the oldest method, as well as the one that most hobby reloaders use. Casting uses a lead furnace to melt the bullet alloys, mould handles, a mould for each weight, shape, and caliber of bullet, then a sizer and lubricator device to correct the diameter and apply a thick bullet lubricant.
   
   
   
2. Machining from solid materials requires a large investment in precision machine tools but is more precise than casting. It is slow, and subject to tool wear, chatter, and machine variables and is used only by a few custom bullet firms, or sometimes to build a prototype bullet.
   
   
   
3. Swaging uses room-temperature materials that can include solid, jacketed, or lead, plastic and powdered metals. The tools are a high pressure press that can flow the bullet materials without melting them, and diamond-lapped, high precision dies with matching punches that instantly give the materials their final dimensions (shape, caliber and even internal constructions) with no further processing, lubricating, or sizing.

Five Problems with Casting

The problems with castings are:

1. The process itself involves extremely hot molten metal, which is viewed by some as a toxic process even though it probably is less dangerous to health than breathing the fumes from automobiles in the typical city street. But the main danger is from burns and lead pot explosions: a drop of water, a fly or moth that suddenly drops into the pot, can cause the entire content to fly into the air with an explosive force. Wearing a face mask and other burn protective clothing is not only sensible, it can save your vision and your good looks! With children around, casting bears certain risks that are not present with the cold metal forming technology of swaging.
   
   
2. There is little flexibility for those who like to experiment with bullet shapes because each shape, caliber, or weight requires an investment in a new mould, and the only way you can get custom shapes is to pay for a custom shaped mould. In contrast, swaging offers almost unlimited weights and dozens of styles in a single swage die, based on technique alone. As you add more punches and dies, the possibilities multiply, since you can combine steps on a single bullet to produce shapes none of the parts would have made by themselves.
   
   
3. The time for melting lead, heating the moulds, casting, inspecting, rejecting, sorting, sizing and lubricating, cooling and cleaning up makes it difficult to try a few bullets on a moments notice, whereas swaging can be done in seconds starting with a roll of lead wire and a swage die. The finished bullet pops out of the die ready to shoot, no sizing, lubricating, or other time-consuming operation is necessary for a vast majority of designs, certainly all those which are similar to the cast bullet.
   
   
4. The basic design of any cast bullet is a frozen piece of lead, eliminating the possibility of jackets, partitions, shot-filled cups, multi-part bullets, bonded cores, hollow-base/hollow point combos, and thousands of other innovative designs, whereas swaging allows all of these exciting designs and more.
   
   
5. Inaccuracies can easily result as trapped air or other gases cause unwanted internal bubbles that lead to variations in weight and balance. (The split mould exposed on the open sides to room temperature air with four or five times hotter metal on the other side of the cavity makes it virtually impossible to cast a truely round bullet; high temperature molten lead goes to room temperature on every bullet cast, so that thermal size variation is a built-in factor that is extremely difficult to eliminate.) In contrast, swaging works with precise round holes that are not split down the middle and do not have to be heated and cooled for every bullet. The pressures used are usually 2000 times that which is placed on molten lead when it is poured, eliminating all voids and trapped air inside the bullet core.

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Why Major Ammo Makers Swage Their Bullets

The newer method, and the one used by the major ammunition companies, benchrest bullet makers, and virtually everyone who is interested in making the most accurate bullet possible, is swaging, or pressure-forming. Unlike casting, swaging does not involve heating molten metal, so it simply doesn't have the same toxicity or danger of burns or fire. Moreover, swaging is a very flexible process, allowing one to make multiple variations on a theme with a single set of dies. A single swage die is equivalent to thousands of moulds, since it can make virtually any weight of bullet in many styles. You can even make your own jackets from common materials such as copper tubing, copper strip, or fired .22 cases, and produce bullets that outshoot anything you could buy off the shelf (since you can control the bullet weight, shape, and style precisely for the best result in your particular firearm).

Swaging is much better suited to high-volume manufacturing with virtually no variation from bullet to bullet. Notice that everyone from Blount to Winchester makes their bullets using the swaging method. Recent Speer ads make our point clearly by specifically pointing out precision swaging as the method of production. Of course, swaging has long been the only viable choice for anyone in the commercial jacketed bullet field, with the exception of electro-plated lead bullets (and many of them are first swaged from lead, plated, and then re-swaged in Corbin dies to regain their precision diameter and finish).

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Corbin Swage Tools Work For You,Too!

For years, many hand loaders have been under the impression that swaging was too expensive or complicated for them. The myth has been repeated over and over, sometimes by those who would prefer that you do NOT know the truth (since then, you would know that you could make the same product that you now feel you must pay them to produce for you!). In the years just after the Second World War, right up until the mid-1970's, there was in fact some truth to this. Bullet swaging equipment was, at one time, only built for the benchrest shooter by a few dedicated die-makers, who had to charge the equivalent of several thousand of today's dollars for their painstaking work. World records were set by bullets swaged in these dies. A few firms tried to offer low cost versions but the result was typically very poor, and nearly all of them went out of business eventually. Partly because of the people who tried to cut corners and make cheap swaging tools, swaging got an undeserved bad reputation among shooters who had never tried it, or had only tried the cheaper tools. (The same is true today: a handful of low-end producers do in fact make cheaper versions of Corbin tools, even copying the nomenclature and catalog numbering system. But it has always been easier to copy terminology than quality.)

You can count on Corbin for everything you need in bullet swaging.

Questions....?

We're available Monday through Thursday, from 9AM to 5PM Pacific time. We'd love to hear from you! Just call (541) 826-5211 or FAX (541) 826-8669. Or write to:

• FAQ
  
  
• Build a "kit" for any bullet
  
  
• A basic starting package
  
  
• Die set recommendations
  
  
• Replacing cast bullets
  
  
• Making jacketed bullets