The 7.65×53mm Mauser, also known as the 7.65 Argentine, is a first-generation smokeless powder rimless bottlenecked rifle cartridge developed for use in the Mauser Model 1889 rifle by Paul Mauser of the Mauser company. It is also known as 7.65×53mm Argentine, 7.65×53mm Argentine rimless, 7.65mm Argentine, 7.65×53mm Belgian Mauser or 7.65mm Belgian and 7.65×53mm Mauser.
The 7.65×53 Mauser cartridge was adopted by the Belgian military around 1889, so the 7.65×53 is commonly known as the 7.65 Belgian Mauser. Shortly thereafter the 7.65×53 was adopted by several South American countries, including Argentina, so it is also known as the 7.65mm Argentine, particularly in North America.
The 7.65×53 has a rim diameter of .474″ and a case length of 53mm (2.09″). 7.65mm translates to .303 caliber in English usage, and the 7.65×53 uses the same .311″ diameter bullets as the .303 British.