Silencers, called sound suppressors in the military, have long been used for special operations, by intelligence agents, and for other such specialized missions. They have been fitted to pistols, rifles, and submachine guns.
Sound suppressors were first introduced to the United States in 1909 by Hiram Maxim, the son of the inventor of the first practical machine gun. He dramatically improved his design in 1910 and silencers became popular amongst back yard sport shooters. The first historical record of the use of silencers by the military was an expedition by Black Jack Pershing in his attempt to capture Poncho Villa. He reportedly brought two M-1903 Springfield rifles equipped with Maxim silencers. There is also evidence that some of these suppressed Springfield rifles were used in WW I, however the nature of the trench warfare did not give any significant advantage to the use of silencers.
Silenced Weapons in World War II: The High Standard HDM
The most significant advances in the use of sound suppressed weapons were in World War II. Several notable weapon designs were developed and used by the allies in this conflict. One of the most famous and long lived was the High Standard HDM. The pistol was developed for the Office of Strategic Services (OSS) and was used by its operatives throughout WW II. It was based on the High Standard .22 caliber pistol, fitted with an integral sound suppressor, 7.75 inches long and one inch in diameter. The pistol had a ported barrel surrounded by wire mesh; in front of the barrel were a series of wire mesh baffles. The sound suppression levels were in excess of 20 decibels, which was quite good for that era.
The pistol was such an effective weapon for covert operations that it was used extensively by the Central Intelligence Agency (CIA) after WW II and also by operators in Vietnam. It was reportedly carried by the teams in the aborted Iranian hostage rescue.
The next significant design came out of Great Britain. This was the Welrod silenced pistol, primarily used by the British, but also used by the American OSS. The Welrod was produced in both 9mm and .32 ACP. The magazine formed the pistol grip and held 5 rounds. The balance of the pistol was a tubular apparatus 1.25 inches in diameter and twelve inches long. The rear contained the bolt and firing apparatus. The mid-portion contained a ported barrel while the front of the tube contained baffles and wipes.
The Welrod was noted for being extremely quiet, but had a limited effective range of 25 yards.
Following the Welrod, in the U.S., U.K, and other countries, many pistol models were used for covert operations with silencers designed to match their mission profile.
German Silencers in World War II
The German army fielded suppressors for a 9mm Steyr pistol, the Luger P-08 and the Walther P-38. These were used by night patrols and listening posts mostly in the Eastern Front. The Germans also fielded a muzzle mounted suppressor for their Mauser 98 sniper rifles, which was quite effective at hiding the source of the shot without interfering with velocity or accuracy.
For suppressed weapons with a longer range, the DeLisle Carbine in .45 ACP, or the Sten Mark IIS and VIS submachine gun were used. The DeLisle carbine was manufactured using an Enfield bolt action receiver fitted with a modified Thompson submachine gun barrel and a magazine well that would accept modified M-1911 .45 magazines with a capacity of seven rounds. The silencer used a series of baffles attached to rods to maintain their alignment.
The bore of the silencer was eccentric towards the top of the silencer tube, similar to the Maxim design.
The Sten Mark IIS and Mark VIS incorporated an integral suppressor, which basically extended the length of the already tubular Sten gun. The suppressors were outfitted with a leather cover because of rapid heat build up. Because of this tendency, they also were generally not fired in the full auto mode. Heat and vibration tended to cause bullet strikes against the baffles. The suppressed models were produced at the request of the British Special Operations Executive for use by their teams in occupied Europe. (See Sten Submachine Gun for other photos and information about the silenced Sten.)
There are also some references to a suppressed M-3 Submachine Gun (grease gun) in .45 ACP being fielded, as well as references to a suppressed M-1 Carbine being tested in WW II. Information about these items is very limited in the available references.
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