458 Express

458 Express

Clinton hunted a lion and elephant with his .458 Express

Photo by Clinton Bauermeister

New caliber design process

Introduction.

As an avid reloader and hunter the quest for the perfect combination in rifle and caliber will always be a dream. Choosing a firearm and caliber is a very enjoyable experience. Even more rewarding is the ultimate step a person can take, to design and develop a new caliber!

I once called a very well known attorney to register a patent. In my mind I was absolutely convinced the product I created was unique and required a patent to stop other from cashing in on my design. The questions and answers I received from the attorney taught me a valuable lesson - "Do not think because you have an idea it is a product entirely owned by you, do research and take time and effort to look for other similar exciting products on the market".

Where to start?

The book "Cartridges of the World" surely is a comprehensive compilation of what is happening in the caliber world, provided you sit with the latest edition off course. Start with the latest edition of "Cartridges of the World" and look for the caliber you intend to design, I can assure you, your readings in this book will bring you much further than most other sources in the market place. The well known military orientated "Janes" publications are brilliant, but unfortunately extremely expensive. It is a good idea to at least try and start your research with these books.

What constitutes a new design?

As we know a caliber, not listed by the major ammunition manufacturers, are called "wildcat calibers". It is a wonderful prospect of designing a wildcat and the caliber is taken up as a standard caliber by the marketplace. I am sure many of us would like to be connected to such an experience. Your design should at least have the following criteria:

Intention and goal of your caliber's ballistics.
Drawings of the case design.
Design criteria for the reamer.
Drawings of the reamer.
Design of the reloading dies.
Develop a brass case and record the specifications with all the above taken into account.
Barrel and groove specification of the firearm in mind, with the action limitations taken into consideration.
Develop and built a rifled action.
Reload the first ammunition for test fire purposes. ADHERE TO SAFETY MARGINS AT ALL TIMES!!!
Have the developed barreled and action with the ammunition tested for pressure purposes.
Obtain a Pressure Test Certificate from the Buro of Standards. (In South Africa it is the SABS).
Register the caliber with your relevant legal departments, in South Africa the SAPS.
Built a complete rifle.
Develop a range of reloading data and record all data very accurately.
Publish your design and specifications.
Label the design / development - Initial names and end product names might differ and it is important that a clear description will then be given for the name to be used for the end product. Choose a name unique and to the point.

General

It is was no surprise when I started my research on ballistics many years ago that there are numerous very confusing names used for calibers. The basis for giving a name is "undefined" and names are given at random according to developers liking. No rules are cast on stone on this one.

I found that many calibers listed as obsolete for a number of years would re surface after a while with a new name but not necessarily new specifications. This is especially relevant to the "new" American designs for "old" British design, an example is the 6x57mm now only known and available as a .244 Remington. Same salad - different dressing.

Another interesting aspect is the fact that imperial measurements do not necessarily match the metric dimensions of the caliber, here the beloved 404 Jeffrey is a good example. The bore dimensions are indeed .423'' or rather 10.7442 millimeters for the 404 Jeffrey. In handgun calibers a very common example is the 9mm range, all firing bullets of .356 up to .358 caliber, but who would then categorize the .38 Special as a .357 caliber?

Naming conventions are also "adopted" rather than purely stating a caliber name specifically. The "460 Weatherby" or my favorite "450 Nitro Express" are good examples of this style. These two mentioned both shoot a .458 diameter bullet.

The very well known and trusted 470 NE actually shoots a .474 and .475 diameter bullet.

In many instances the case of the caliber plays a role in the name of the caliber, we talked about the .577 Snider in the history chapter of this book and then the 577/450 Martini Henry rifle which was indeed a .577 Snider case necked down to accept a .45 caliber bullet.

On the cases it is also worth our while to note that the "R" for Rimmed and "Flanged" are used with a set rule as mentioned above. In general it is commonly accepted that the cases are Rimless and if otherwise, a letter like the "R" would specify the case design. Once again my favorite and inspiration is a brilliant example; .375 Holland & Holland - rimless and the .375 Flanged Magnum as a flanged case of very much the same design in rimless. (Take a look at the Norma Catalogue pictures)

Take a look at some of the .458 Calibers in use!

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