British firearms-enthusiast and engineer William Godfray De Lisle designed his De Lisle Silenced Commando Carbine around the action and stock of the Mk. III Lee-Enfield rifle. Chambered in .45 ACP and accepting slightly-modified .45-caliber Colt 1911 pistol magazines rather than the Lee-Enfield’s standard 10-round .303 magazine, the De Lisle boasted an 8.2-inch integral barrel sound-suppressor. The suppressor allowed propellant gas from the rifle’s .45 cartridge to bleed out of the barrel, quieting the sound of the round leaving the muzzle.
It was never a very numerous weapon, but the De Lisle Silenced Commando Carbine proved to be just the thing for commandos needing to silently kill a few sentries as they infiltrated enemy lines.
De Lisle, whose day job was with the U.K. Ministry of Aircraft Production, had previously built an integral suppressor for his .22LR Browning SA, which he used to hunt small game. De Lisle’s neighbor Maj. Sir Malcolm Campbell, of the Office of Combined Operations, heard about the silenced hunting rifle and felt it might make a good clandestine weapon.
Prototype development ended in 1942. But after a few demonstrations, the government requested a nine-millimeter version. This was, at the time, the most commonly-available rimless pistol cartridge. However, the velocity of the nine-millimeter round proved to be too high. The suppressor couldn’t sufficiently reduce the prototype’s report.
In other words, the nine-mil De Lisle was just too damned loud.
De Lisle suggested re-chambering the carbine to fire the subsonic .45 ACP. This proved to be extremely quiet. De Lisle adapted the first .45 ACP carbine from a Thompson submachine gun barrel and the action from a Lee-Enfield. De Lisle and Campbell submitted the design and prototype to the Board of Ordnance for evaluation. Because the carbine was a project of the Office of Combined Operations, the government fast-tracked production. The Ford Motor Company produced an initial batch at its Dagenham works.
De Lisle applied for a patent for the suppressed carbine in May 1943, but due to the weapon’s clandestine nature, the government did not grant the patent until after the war in July 1946.
The De Lisle boasted better accuracy than the competing STEN Mk. II(s) and was marginally quieter. The government placed an order for 500 with the Sterling Engineering Company. Production began in the summer of 1944. The carbine had a 7.45-inch barrel, two inches of which fit inside the Lee-Enfield’s action. De Lisle and Campbell shortened the bolt and added a new .45 ACP extractor. They also developed a new magazine housing to take Colt 1911 magazines.
The men fashioned the suppressor tube from steel. The suppressor featured an initial expansion chamber followed by 10 or 13 baffles making up a continuous spiral and aligned by two rods on either side of the bullet channel.
Sterling manufactured just 130 De Lisle Silenced Commando Carbines before the government canceled the order in December 1945. The De Lisle was truly a niche weapon. Also, the suppressed STENs were cheaper, easier to manufacture and better suited for general clandestine operations.
The majority of the De Lisle carbines had standard wooden stocks, but Sterling also developed a paratroop version with a folding stock. Only two of these paratroop De Lisles were ever made.
The De Lisles saw a lot of combat — considering how few existed. The Special Operations Executive carried them into battle in Northern France prior to D-Day and against the Japanese in the Far East. Quiet and accurate up to 200 yards with no muzzle flash, the De Lisles excelled at killing sentries during infiltration missions.
The weapons saw combat through the Korean War and the Malayan Emergency. In 1970, the Military Armaments Corporation developed a nine-millimeter carbine it called the “Destroyer” that was inspired by the De Lisle. However, suppressed pistols and submachine guns proved more popular with special forces.
This story originally appeared at Historical Firearms.
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