Nambu Model 1

Nambu Model 1

This early Japanese SMG was not actually designed by Kijiro Nambu, but by an engineer named Tokunaga who was presumably employed at Nambu's Tokyo factory. It was the first in a line of submachine guns offered by the Nambu Arms Manufacturing Company in the 1930s, which were known in Japan as simply the Type 1, Type 2, and Type 3. This model, the Type 1, has the notable merit of being the first production SMG to feed its magazines through the pistol grip. It is unusual that the designer elected to choose a feeding mechanism of this type for this particular gun, as the magazines used were distinctive 50-rounders that had an almost 90-degree curvature to them. This meant that the pistol grip, which housed the magazine well, had to be shaped in a rather awkward way to facilitate for the magazines.

The original intention for this weapon seems to have been as a personal defense weapon for tank crews. On the bottom of the magazine was a small hinged latch that was designed to fit onto a vehicle mount. This feature was probably never used in practice. There was also a detachable angled foregrip apparatus that could be fitted underneath the barrel, but contemporary marketing depicts the weapon without this.

Internally the operation is very unusual for a submachine gun of its time. The most notable eccentricity is the placement of the return spring around the barrel rather than behind the bolt. The bolt is latched on to the spring and when the bolt is blown back, the spring pulls it forward toward the breech. Housed in the gun's rear section in place of a return spring is an unusual air-compressed spring buffer device. The Nambu SMG has no conventional cocking handle, and instead the entire barrel shroud is manually retracted to cock the gun.



The air buffer system of the Model 1 SMG.

The Imperial Japanese Army trialed this SMG, along with a few other designs, in the mid-1930s but did not adopt it. The IJA at that time were not very interested in submachine guns and there was no place for them in their infantry doctrine. The Navy, which was decidedly less conservative than the Army, was interested in issuing SMGs to Marines and decided to order a small batch of the Type 1s; it is said that this order totaled at only about 50 guns. These weapons were nonetheless fielded, probably experimentally, by IJN Marines in Shanghai during the invasion of China in 1936.

Also worth noting is that this was probably the only SMG in Japanese history to be offered for export. Nambu, being a private firm, tried to tap into the international market for a short period, with little success. This gun was marketed as the "Model 1" and elicited some interest in Britain, where the Small Arms Committee ordered a test model. It was considered by the British as a potential gun for tank crews but was quickly rejected after short, informal tests by the SAC, who felt the magazine was too awkward and the 8mm bullet was too weak. It is inevitable that the chambering put off any potential European customers, as the 8mm Nambu bullet was used only by the Japanese. Nambu's hopes at achieving export sales were dashed in 1938, as Japan's increasing commitment to the Chinese war meant that all military industry was required to supply the war effort. This was further compounded by the outbreak of the war in Europe, after which Japan officially allied itself with Germany and cut off relations with the rest of the western powers.

Exact production figures for this gun are unknown but the number was considerably less than other Japanese SMGs, which were themselves never produced in particularly large volumes. It seems almost none of the guns survived the war and very few are known to still exist today.