7mm Nambu

Cartridge Data Published On: December 20, 2014 at 11:36 pm by Bullet-Blog and last updated on February 12, 2015 at 11:24 am




The 7mm Nambu (AKA: 7x20mm) is a Center Fire cartridge with a Bullet Diameter of 0.28 in” (7.11mm) that is primarily used in Pistols. The 7mm Nambu originated in Japan in 1929. The 7mm Nambu also has a case length of 0.78 in” (19.81mm) and an overall length of 1.06 in” (26.92mm).


The 7mm Nambu Cartridge, is a cartridge of Japanese design created in 1929 and used in the second World War as the primary cartridge for the Type B Nambu Pistol, a semi-automatic side-arm carried by Japanese Armed Forces, although it was never officially adopted by the Japanese Military. The 7mm Nambu is a compact center-fire bottle-necked pistol cartridge that resembles a 7.8mm Bergmann cartridge in appearance, in a much smaller package and only providing extremely modest velocities and muzzle energies, far lower than that of even the .32 ACP, a cartridge similar in size and dimension. A larger version of the 7mm Nambu, called the 8mm Nambu was available for the larger variations of the Nambu Pistol and offer nominally better ballistics, although still weak for its size compared to many similarly sized cartridges such as the 7.62mm Tokarev.

Cartridge Details

  • Year:
  • Origin:
  • Cartridge Type:
  • Application:
  • Bullet Diameter:
  • Neck Diameter:
  • Shoulder Diameter:
  • Base Diameter:
  • Rim Diameter:
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  • Case Length:
  • Overall Length:
  • Primer:
  • 1929
  • Japan
  • Rimless,Bottleneck
  • Pistols
  • 0.28 in” (7.11mm)
  • 0.301 in” (7.65mm)
  • 0.339 in” (8.61mm)
  • 0.351 in” (8.92mm)
  • 0.359 in” (9.12mm)
  • 0.04 in” (0.99mm)
  • 0.78 in” (19.81mm)
  • 1.06 in” (26.92mm)
  • Center Fire (Small Pistol)

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