The 7.62 x 51 mm Ketsurui Zaibatsu is a full-size rifle cartridge found across the galaxy. It is a standard military cartridge for the Star Army of Yamatai and the Reds of Kennewes. Shorthand is 7.62 mm KZ or 7.62 KZ.
The cartridge is older than the Yamatai Star Empire by an untold number of decades. It was the mainstay cartridge of the people who colonized what now are the Yamataian and Nepleslian star systems. The GP-1 Assault Rifle, produced by the millions, is the most common firearm to utilize the cartridge, though other weapons also use it, such as the S300 Hunting Rifle "CCR" and Zen Armaments Marksman Rifle vz. 1.
The 7.62 mm KZ is the baseline rifle cartridge in the galaxy. It is known for its flat trajectory, adequate projectile speed in common loads of the cartridge and good penetration. Depending on the weapon and cartridge load, the projectile can deliver killing wounds at distances of up to 1,000 meters.
This cartridge is exactly the 7.62 x 51 mm NATO round.