Making Your Own Copper Jacketed Bullets
by Randy Swart
I thought I would throw in a little section on making your own copper jacketed bullets. It won't be in any great detail, but you will get the basic idea and hopefully find it understandable and interesting.
The process of making your own copper jacketed bullets is a little different than the conventional method of melting lead into a mould and casting them.
When casting lead bullets, after they have cooled from the mould, you actually force them thru a resizer that makes the lead casted bullet SMALLER in diameter and also adds lube depending on the bullet style. So the bullet starts out just a little bigger in diameter prior to the resizing step.
The following picture is actually the components and copper jacketed bullet as it goes each step of the process. The process of making copper jacketed bullets is referred to as SWAGING. The reason for this, which is also the difference between this process and casting bullets, is that the bullet diameter actually INCREASES as a result of each of the swaging steps.
In the background, you see a piece of lead wire that is purchased on a wire spool. It comes in 25 lb spools which provides 7000 grains of lead wire per pound. Therefore, if you were making 70 grain bullets that required 45 grains of lead each, ( because the copper jacket has weight as well , totaling the 70 grains ) then you would have enough lead to make approximately 155 bullets per pound of lead wire. There are moulds that you can purchase to pour your own pieces of lead to swage into lead cores. That brings us to the next part of the picture.
There are 4 items in front of the lead wire, and starting from left to right, the first item is a lead core. This lead core was swaged, that is, put under great pressure in the swaging press to create a lead core that has a particular weight and diameter. The lead wire is purchased with a .185" diameter and the finished lead core has an approximate diameter of .191", increasing in diameter. At this point in the process the diameter of the finished lead core is not critical so long as it fits down into the copper jacket, which brings me to the next step.
The next item, to the right of the lead core is a copper jacket. The Copper jacket is basically a copper "cup" that has a thicker base than the side walls and in this case ( J4 jackets ) the wall actually has a taper. The lead core is dropped into the copper jacket and then inserted into a core seat swaging die. There are typically 3 dies and top punches for swaging copper jacketed bullets. These dies are used in a swaging press, much like that of a reloading press. The lead core is then swaged into the copper jacket under a great deal of pressure, tens of thousands of pounds per square inch ( PSI ) . Under this much pressure, the lead core actually "flows" and is pressed out against the inside walls of the copper jacket, enough so to actually increase the diameter of the jacket ever so slightly. Again , as I said , swaging increases the diameter. The other concept that comes into play here is that the copper jacket is somewhat elastic. So when the lead core is swaged into the jacket and the diameter of the jacket is increased, the jacket has a natural tendency to want to spring back to its original size, the elasticity. This causes the jacket to "grip" the lead core.
The picture below shows my swaging press along with a home made tray with 100 copper jackets with lead cores in them .. the jackets that are upside down are the ones that I have already swaged the lead core into , and the others with the opening up, are still needing to be swaged. The other reason for putting the finished ones upside down is because then they will be in the correct orientation for the next step, pointing.
I wanted to add as a side note, that the top punch holder was made by myself on my metalworking lathe in my garage. The top punch holder is the piece on top with the brass locking ring on it . I made several of them because for each of the 3 steps, the top punch holder has to be adjusted. This can prove to be very time consuming and has an adverse affect on consistency. Therefore, I made one , with a brass locking ring for each step of each bullet weight / diameter of copper jacketed bullet that I would be making. The next picture would be of a completed bullet which is the last of the 4 items in the first picture. A different die and top punch is utilized for this step .
Making copper jacketed bullets is not overly difficult, however, there are little tricks and tips. One of the most important thing is consistency in each of the 3 steps. Also the amount of swaging lube is important as the bullet jacket is under great pressures and excessive lube can cause hydraulic dents in the copper jackets.
This next picture is a set of 7mm dies. The first die is for making the lead cores, the second for seating the core, and finally and one of the most important dies, the bullet point die. Of these dies in this 7 mm die set, I made the core die and core seating die and punches. However, I only made the basic die and punches, and the final dimensions were honed in great precision by Dave Corbin in Oregon. Honing with that kind of precision requires a machine such as a Sunnen honing machine which costs upwards or 50,000 dollars or so.
Again, its not an overly complicated process, but requires a great deal of attention to detail and consistency in steps. So much so that if I'm planning on making more than 100 bullets at one sitting, then I will make all the cores at one sitting and die setup, the same holding true for the remaining steps and setups. This is not as critical for me as it used to be because as I stated earlier, I have made top punch holders for each caliber / bullet weight. This improves the consistency between setups. If you learn to make this bullets properly , you can end up with a target like the one shown below shot at 100 yards. These are 5 shot groups measuring 0.205" and 0.260" over bullet diameter. Obviously your rifle has to be capable of such a grouping as well as ones ability to "shoot the wind" .
Thanks to all for letting me share this information with you . I hope that it was as much a pleasure for you to read as it was for me to share. I also hope that you learned a few things about making copper jacket bullets and please feel free to email me about any of the information presented or questions that you might have regarding the process. One a final note, in case you might be interested in making your own bullets. This equipment; the swaging press and dies, cost approximately 500-600 dollars .. J4 Jackets vary in price depending on caliber and how many fit into a "bucket" . Again, you can contact me at RSwart1@twcny.rr.com for further info if you are interested in giving it a try ..