Type Ko Rifle

Kokura Arsenal · Rifle · Prototype · 1932

Also known as: Experimental Automatic Rifle Type Ko, Japanese Pedersen Rifle, Shisei Jido Shoju Ko-go

Overview

The Type Ko was an experimental Japanese self-loading rifle trialed by the Imperial Japanese Army in the early-to-mid 1930s. It was a licensed adaptation of John Pedersen's toggle-delayed blowback rifle, fitted with an Arisaka-style front cap and sight and fed from a rotary magazine chambered for the 6.5x50mm Arisaka cartridge. Developed in competition with the rival Type Otsu and Type Hei designs, it was never adopted for service.

Specifications

Weight (empty)4080 g (143.9 oz)
Overall Length1149 mm (45.24")
Barrel Length610 mm (24.02")
Action TypeDelayed Blowback
Firing MechanismHammer Fired
Trigger TypeSingle Stage
Magazine Capacity10 rounds
Magazine TypeRotary
Effective Range500 m (547 yd)
Barrel RiflingRight Hand
Frame MaterialSteel
Barrel MaterialSteel
Stock MaterialWood
FinishBlued

Calibers

Features

Production

Production years: 1930s

Small number of prototypes built for Imperial Japanese Army trials; never mass-produced.

Origin

Country of origin: Japan

Designer: John Pedersen

Notes

Japanese designation shitsei jido shoju Ko-go (試製自動小銃甲号). Exact production figures and some physical specifications are unconfirmed; physical dimensions are estimated from the parent Pedersen rifle design.

Background

After his .276-caliber toggle rifle lost to the Garand in US trials, John Pedersen took the design abroad, and Japan was among the nations that tested it. The Japanese swapped Pedersen's en-bloc clip for a rotary magazine and grafted on an Arisaka-style muzzle cap, but the Type Ko never beat out its Type Otsu and Type Hei rivals.