The JE-1 Japeradicator carbine is a prototype carbine.
The JE-1 (with “JE” standing for “Japeradicator”) was a submachinegun designed by a worker at Douglas Aircraft named C.C. Howlett. While his weapon would now be regarded more as a PDW (Personal Defense Weapon), at the time of its inception it was meant to be a small stockless submachinegun to use the then new .30 Carbine cartridge, which the US Army hoped would be a round which was lighter and more effective than the .45 ACP when fired from longer barreled weapons. The JE-1 was a selective fire weapon based on short blowback operation, with a barrel that recoiled slightly much like that of a pistol, but not as far. The upper receiver of the weapon was fashioned largely of stamped steel, with a lower receiver of aircraft aluminum. And a wooden pistol grip and fore-end/heat shield. A simple thumb lever controlled the operation of the weapon, and the barrel was a short 12-inches, finned on the rear third of the barrel for cooling. As stated before, the barrel had a lower wooden foregrip/heat shield, with a steel, ventilated shield on top of the barrel; the barrel protruded only a fraction of an inch from this affair. External steel parts were blued, the aluminum was left in natural metal, and the wood laminated. No tools were required for stripping. The weapon was designed to be used with two hands, but could be fired with one hand. For a prototype, the JE-1 was exceptionally well made, but it was a bit on the heavy side.
Unfortunately, though the Army took a long, hard look at the JE-1, and even extensively tested it, they requested several changes, something Mr. Howlett had little money to do. It was later determined that the JE-1 offered no significant advantages over the M-1 Carbine, and furthermore could not have a grenade launcher or bayonet mounted. Though the OSS was reportedly quite interested in the JE-1, the Army dropped interest in the weapon, and the end of World War 2 effectively killed the JE-1 completely.