The rifle and handgun cartridges designation is usually expressed by the agreed size of the barrel bore diameter (caliber) or of the bullet (projectile) complemented with additional indication or symbol. The numerical markings most often use either European or Anglo-American system.
The European designation is the product of two numbers. The first number indicates caliber (barrel bore diameter) and the second number indicates cartridge case length in millimetres, e.g. 7 x 64 or 8 x 57 JR and the like.
At the American and English designation the first two numbers indicate the bore diameter in the hundredth or thousandth of an inch with the abbreviation of the first manufacturer (of given cartridge) name. For example .308 Win. stands for 30 hundredth of an inch = bore diameter and W = Winchester. (1 inch = 25.4 mm). Eventually other numbers indicating the year of origin, e.g. for given example 308 W the number „8“ the last digit of the year of introduction - 1948. Or for caliber 30-06 the first two numbers mean 30 hundredth of an inch = bore diameter and the second two numbers 06 is the year of origin - 1906. Or more often the second two numbers used indicate the weight of powder load, e.g. 30-30 (30 hundredth of an inch is bore dia. and 30 grs powder load). The powder load is understood to be the powder load weight given in grain unit (1 grain = 0,064 grams). Sometimes the third number is for the purpose of cartridge definition at the manufacturer’s facilities etc. A consistent Anglo-American caliber identification should be for example 0.223 Rem. This was gradually simplified and zero at the beginning is not entered any more and it is written only as .223 Rem or only 223 Rem. Besides the abbreviation denominating the first manufacturer Win = Winchester, Rem = Remington, MSch = Mannlicher Schönauer etc. the rifle cartridges are further identified by some other symbols:
R = (Rand) cartridge case having a rand
S = (Stark) enlarged bullet diameter for 8 mm cal.
S.E. = (Super Express) increased bullet velocity
Mag. = (Magnum) powerful cartridge
N.E. (Nitro Express) smokeless powder used
I or J = (infantry) – military origins of the caliber
The cartridges identified with R are typically designed for break-action firearms, e.g. 7 x 57 R or 7 x 65 R. With 8 mm cartridges we must pay a proper attention to the careful differentiation. Originally there was development of a military caliber cartridge 8 x 57 I. (Mauser cartridge mod. 1888). With the objective to obtain a more powerful cartridge that cartridge has been gradually changed with regard to the bullet diameter bordering with the firearm’s safety. This necessitated not only an introduction of larger bullet diameter, but also larger barrel bore dimensions. These conditions brought forth Mauser cartridge Mod. 1905 cal. 8 x 57 JS (S = stark). Therefore, a larger diameter bullets and firearms with a corresponding bore are identified with the letter S.
8 x 57 J cartridge with a groove for the repeating rifle
8 x 57 JR cartridge with a rand for the break-action firearm
8 x 57 JS cartridge with a groove for the repeating rifle with a larger bullet dia.
8 x 57 JRS cartridge with a rand for the break-action firearm with a larger bullet dia.
Warning! J and JS cartridges (or JR and JRS) are not interchangeable and their use in the wrong firearm can have tragic consequences. Cartridges with larger bullets dia. have for a better differentiation the primer identified with a red colour. When using the 8x57 JS cartridge a mistake is not dangerous, but results in an inaccurate fire. Reverse mistake or confusion is however a very high-risk matter with a danger in the firearm destruction.
Comparison of identifications between American and European system of calibers for individual cartridges:
||cartridge for rimfire rifle - long
||cartridge for rimfire rifle - short
|22 WMR - Winchester Magnum Rimfire
||cartridge for rimfire rifles - extra long
||5,6 x 35 R (Vierling)
||5,6 x 36 R
||5,6 x 43
||5,6 x 45
||5,6 x 52 R
||6,2 x 51
|25 - 20 Win
||6,5 x 33 R
|25 - 20 SS
||6,5 x 41 R
|25 - 35 Win
||6,5 x 52 R
||6,9 x 64
|7 mm Rem Mag
||7 x 63
|300 Win Mag
||7,62 x 66
||7,62 x 51
|30 - 30 Win
||7,62 x 51 R
|7,62 Rusian (Lapua)
||7,62 x 54 R (former mod. 59)
||7,7 x 56 R
|30 - 06 Spr
||7,62 x 63
||7,62 x 39 (former mod. 43)
The above comparison of caliber identification is made only for information, because in practice there is always applied the original caliber designation and that with the identification as made by the first manufacturer (originator) or as specified by C.I.P. For the possibility of mass production of firearms and interchangeability of use of both firearms and ammunition of the same caliber, but from different manufacturers, there was a gradual unification of calibers and standardization of dimensions of cartridges and cartridge chambers.
At the turn of the 19th and 20th century there were, especially in Germany, plenty of manufacturers of cartridges. Each of these manufacturers was involved in production of cartridges having variations in shapes and dimensions and each of them with its own labelling. This resulted in situations that often the cartridge designed for a certain firearm cannot be properly inserted into the cartridge chamber. A certain chaos in identification, cartridge dimensions and shapes concerned mostly Germany. This was the reason that starting with 1909 there was a gradual unification of cartridges shapes and dimensions and their standardization. The first standardized cartridge became the cartridge with designation 8,15 x 46 R. For the purpose of cartridges standardization they established the German Commission for Standardization composed of representatives of proof houses and ammunition manufacturers, which closed its activities just shortly before WW 2, when the results of their work were included into the Act on Firearms and Ammunition. The German standardization of cartridges had its historical merit in unification of shapes and dimensions and cartridges itself. The most important contribution was the unification of cartridges identification using the metric system composed of the product of a rounded bullet dia. (barrel bore) a the cartridge case head in mm (diameter x length), which is used now by the whole world.
Today the standardization is carried out under the international convention of C.I.P. (Permanent International Commission for Firearms Testing), which is an executive body of the Brussels Convention established in 1914. The Czech Republic is the C.I.P. member since 1965. Accepted standards are generally respected even by non-member countries of this international convention. A similar situation applies also for the U.S., which however are not a member of the C.I.P. and where the state does not assume any guaranty for the safety of manufactured firearms and ammunition and any complaints are dealt with according to commercial practice. The USA faced the same problem as Europe, and that is a different dimension of cartridges going along with individual manufacturers. The unification of dimensions has been necessitated by the need to provide uniform ammunition for the U.S. Army. For fulfilling this task the Small Arms and Manufacturers Institute (SAAMI) was founded in 1913. After military ammunition unification this was also done for the civilian sector and above organization was in 1926 transformed into the Sporting Arms and Ammunition Institute, which provides not only for unification of dimensions, but also for many other standards and specifications concerning ammunition. The SAAMI and C.I.P. cooperate closely.
Source: Dr. Ing. Jiří Hanák M. Sc.