Wilhelm Brenneke was a brilliant German cartridge designer and still famous in Europe for his development of slugs for use in shotguns. He also constructed a very modern line of rifle cartridges with the most popular bullet diameters from before the turn of the century, but with a larger powder space than the then “standard” length of 57 mm.
The first was 8x64 from 1912 which was designed in a an attempt to get a government contract for a more powerful military round than the 8x57. The attempt was in vain, but as the 7x57 was already popular Brenneke also constructed the 7x64 in 1917 - 40 years before the almost identical .280 Remington was introduced. Designed solely as a hunting cartridge the 7x64 is very widespread in Central Europe as several countries here have banned the use of military calibers for hunting.
To the handloader the 7x64 is a very versatile cartridge with bullet weights available from 80 to 180 grains. You could call it a European .270. As the powder space of the two cartridges is almost identical, the differences in performance are purely academic when it comes to bullets of equal weight. However due to its slightly larger bullet diameter - .284” compared to the .270’s .277” - the former has a slight edge when heavy bullets are needed for large species. The 7x64 is adequate for all species on the Northern hemisphere - including the big bears, provided a heavy bullet of good construction is used.