|The following is based on developer test content cut from Fallout 3 and is not canon.|
The test gun is visually identical to the 10mm pistol. Due to its name and its nature as cut content, it can be assumed that the weapon was placed in the game files for developer testing purposes. Additionally, its traits in the GECK lists the same flare effect as the grenade launcher, another cut weapon.
The test gun can fire a total of about 556 rounds, the equivalent of 47 reloads, from full condition before breaking.
This item cannot be obtained except through the use of console commands.