The Welrod is a British bolt action, magazine fed, silenced pistol devised during World War Two at Station IX - the Inter Services Research Bureau - based at Welwyn, UK, for use by irregular forces and resistance groups. It was not a mass produced weapon, only around 2,800 being made.

It was used primarily by the SOE but was also used by the OSS and was extremely silent, being almost inaudible when fired. Examples were made in 9 x 19 mm Parabellum and .32 ACP, with capacities of 5 rounds in the magazine (more rounds could be loaded, but it was not reccommended). The Welrod took the form of a 1.25 inch diameter cylinder about 12 inches long. The rear of the cylinder contained the bolt, the middle the ported barrel and expansion chamber of the silencer, and the front the baffles and wipes of the silencer. There is a knurled knob at the rear that serves as the bolt handle, and the magazine forms the pistol grip. The Welrod was provided with sights (flourescently painted for low light use), and had a maximum range of 25 yards, but was intended for use far closer. In fact, the muzzle end of the gun had a concavity that was designed to allow it to be fired in direct contact with the target, which reduced the sound levels even further.

The ported barrel of the Welrod served two purposes; it released the powder gasses gradually into the rear of the silencer, reducing the sound of firing, and it reduced the velocity of the bullet to subsonic speeds (this was especially important in the 9mm version since the standard 9mm loading is supersonic). The baffles and wipes that follow the barrel serve to further slow the gasses of firing, releasing them over a long period of time and avoiding the sharp explosion that occurrs when high pressure powder gasses are suddenly released to the atmosphere.

The Welrod used a bolt action design because it was simple, reliable, and quiet. Revolvers are not suitable for silencing because the gap between cylinder and barrel releases high pressure gas which cannot be silenced; semiautomatic pistols have many parts that move when firing and make a loud and distinct sound. The bolt action has only the noise of the firing pin hitting the primer, and the bolt can be cycled quietly, if needed. While single shots were the norm for the missions the Welrod was used in, the action could be cycled and a new round ready to fire in less than a second.

The Welrod was a "sanitized" weapon, meaning that it had no markings indicating its manufacturer or country of origin; all it was marked with was a serial number and some inscrutable symbols and letters (likely inspection marks). The Birmingham Small Arms Company has confirmed that they manufactured some of the Welrod pistols, but claims they put no markings at all on them, so the markings were likely added by the British military after delivery.

For use at longer ranges the silenced version of the Sten gun and the silenced De Lisle carbine were used.

The Welrod was widely used in Denmark during WWII, and is reported to have been used during the Falklands War of 1982.

The name Welrod comes from the custom that all the clandestine equipment devised at Station IX in Welwyn had names starting with Wel, e.g, Welbike, Welman

For a description of other weapons designed to be used by insurgent and resistance fighters, see insurgency weapon.

External links:

Welrod Silenced Gun A Danish site with research into the production and use of the Welrod