Cartridge Naming Conventions

This is not a post about a group of manufacturers getting together to decide what to name a cartridge, to my knowledge that has never happened. Though perhaps it should have.

There has always been a lot of confusion surrounding the naming of different cartridges, especially ones from English speaking countries.

The Europeans are good at adopting universal standards, the Metric System, the Euro, the use of Passports. This includes their cartridge naming convention. In Europe the cartridges are named by the diameter of the bullet and the length of the cartridge case. For instance the 9mm Luger (also known as the 9mm Parabellum) is officially known as the 9x19mm. The diameter of the bullet is 9mm and the case is 19mm long. The .380 ACP which is also known as the .380 Automatic (not to be confused with the .38 Automatic) is known as the 9mm Kurz (German for short) or the 9mm Browning Short in Europe. The metric designation is 9x17mm.
Another example would be the 7.92 x 57 Mauser (sometimes referred to as the 8 x 57 mm Mauser).

The Americans and Brits have a different way of going about it. In England they may use the European standard or they may just give the cartridge a name that may or may not reflect the size of the bullet or cartridge. For instance the .300 H&H Magnum does not really have a .300" bullet diameter it is actually a .308/.309" diameter.

In America the rules were thrown out the window, although things have standardized a bit over the last 60 years or so.
During the early days of cartridge ammunition, when Black Powder was still being used, the manufactures would name the cartridge by the diameter of the bullet and the weight of the black powder charge followed by the name of the inventor. 
For instance the 45-70 Government is a .45 cal bullet (not really, it is actually a .458" diameter) that was originally loaded with 70 grains of black powder. Now we know that every cartridge has different loadings with different bullet weights which also require different powder charges, so this convention didn't work all that great. 
Take for instance the .30-30. You would think that this was a .30 cal bullet with 30 grains of black powder, not really. The 30-30 started life as a smokeless powder cartridge, originally called the .30 Winchester Center Fire (.30 WCF), but manufacturers like Marlin did not want to put "Winchester" on their barrels when they chambered their rifles for the cartridge, so they used the name .30-30  and it stuck.
The same confusion applies to the 30-40 Krag. the Krag was also originally a smokeless powder cartridge that used a .308" bullet and did use 40 grains of nitrocellulose smokeless gun powder. The cartridge was known to the U.S. Military officially as the .30 U.S. .
This convention was not universal, some companies used the diameter of the bore or the diameter of the chamber to name the cartridge.

Lost yet? It gets better. Around the turn of the century the U.S. was looking for a better cartridge and rifle for their troops. In 1903 they adopted a new cartridge to replace the 30-40 Krag. This one also used a .308 caliber bullet, but had a longer case and had options on the propellent and charge weights. The U.S. Army named the cartridge the .30-03. the .30 for the diameter of the bullet (which again was actually .308") and '03 for the year in which it was adopted. Three years later the .30-03 was replaced by an even better version which became known as the .30-06, sometimes pronounced "thirty-aught-six" or "thirty-oh-six".

Some confusion also surrounds cartridges like the .38 Special. How is it that a .38 special and a .357 Magnum can be fired from the same gun? Are they not two different sizes? Not really. The .38 Special was originally developed to shoot in converted .36 caliber Cap & Ball revolvers. This required a heeled bullet with lubricant on the outside of the case.

 The case diameter is actually .379" thus the .38 Special name, while the actual bore was .357 - .358" in diameter (which allowed it to be fired in the .36 caliber cap & ball guns). Later on when the .357 Magnum was developed, they used the actual diameter of the bullet/bore in the name and lengthened the case (to prevent the more powerful .357 from being fired in a .38 special revolver).
In the case of the .44 Magnum, the explanation is similar. The .44 Magnum was derived from the .44 Special, which in turn was derived from the .44 Russian, which in turn was derived from the .44 S&W American (which was derived from the rimfire .44 Henry). The .44 S&W American had an externally lubricated bullet with a heel, like the .38 specials, the case diameter was .440 (thus the .44 name) but the bullet was and still is approx .430 in diameter.

There is still one cartridge made in this way, the venerable .22 Long Rifle, whose bullet diameter is actually .223. The European name for this cartridge is 5.6 x 15mm R, the "R" stands for rimmed cartridge.

 Fast forward to modern times, the .30-06 was replaced with the .308 Winchester, which is also known as the 7.62 x 51MM NATO cartridge. Again using a .308 bullet (and a redesigned .300 Savage case), this time the name actually reflects the bullet diameter.
We are getting better at this or so I thought....The 10mm pistol round, when developed was and still is called the 10mm Auto, not the 10 x 25mm which would follow European conventions. One of the newest cartridges on the scene, the 6.8 SPC, is a necked rifle cartridge. The name 6.8 Special Purpose Cartridge does not reflect the actual size of the bullet which is 7mm (.270"), the European name would be 7 x 43mm, but here we call it the 6.8 SPC.....

I am not suggesting the European convention is better, in fact I kind of like the fact that the U.S. still marches to the beat of our own drum.
Metric system, nah.....passports....not necessarily, universal monetary unit, not on your life.



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