Covert Commando: Reviewing the Famous De Lisle Suppressed Carbine

Silencers have been used by law enforcement, military and civilians since the 19th century. Silencers were developed in Switzerland, and later improvements and modifications enhanced the device. Most notable was the design by firearms legend Hiram Maxim who patented his in 1909. With the relaxation in federal proscriptions, they are receiving a new renaissance with American shooters.

Though suppressors are largely in vogue with shooters of contemporary arms, there have been attempts at appealing to vintagers. One of the most ambitious efforts in this direction is a new rendition of the famed British silenced De Lisle “Commando” carbine, originally developed in Britain during World War II. Considered one of the quietest small arms of its type, its reincarnation is manufactured by U.S. Armament Manufacturing in Ephrata, Pennsylvania. It is a faithful rendition of one of the most enigmatic and intriguing arms of its type.

William Godfray De Lisle (1905-­1988) was born in South Africa. He moved to the UK at an early age where he continued his education, eventually joining the Air Ministry in 1935. As a youth, De Lisle became fascinated with firearms, especially silenced rifles. His first essay into the field involved designing and building simple .22 silencers made from discarded tin cocoa canisters, which he and his chums took rabbit shooting.

While working as an engineer at the Air Ministry in 1942, privately, De Lisle came up with his premier silenced rifle, a modified Browning .22 semiautomatic rifle that he patented. He duly took the piece to Major Sir Malcom Campbell of Britain’s Combined Operations who was immediately impressed with the gun, informally testing it in central London to determine if it could be heard by passers-­by. A lack of response to the gun’s report by the unwary test subjects encouraged authorities to continue testing the piece. It passed with flying colors.

Combined Operations Headquarters decided that such an arm, in a heavier caliber could have numerous military applications, so it authorized De Lisle to develop such a silenced carbine. Initially, 9mm Parabellum was the chosen round due to it already being in British service. As it was supersonic, even De Lisle’s utmost efforts to slow the bullet down to an acceptable velocity to achieve a quieter report were thwarted.

It was then decided to alter the caliber to the sub­sonic .45 ACP. Experimental models were fabricated circa mid-­1943 at Bapty & Co., which also had done the work on the 9mm version. The .45 bullet’s slower velocity, coupled with its heavier 230-­grain weight, as opposed to the 9mm’s 146 grains, provided adequate stopping power — even when suppressed. Further tests to prove the gun’s viability were authorized. Results were so promising that 17 were ordered to be constructed for service by the Commandos in France where they were primarily used by combined operations for taking out sentries during coastal raids.

This first small batch of De Lisle carbines was initially produced at Ford Motor Company in Dagenham, East London. They were composed of condemned Mark III SMLE rifle actions and butts mated to Thompson submachine gun barrels. As it was necessary to insert the Thompson barrel some 2 inches into the action, this meant the rifle bolt had to be shortened to that degree. The bolt face was also modified from the flat surface used with the rimmed service .303 rifle round to one recessed that would more effectively accommodate the .45 ACP’s rimless case. A modified extractor was also felt to be needed. The action’s charger bridge was removed and an extended ejector added. The magazine well was modified to accept a U.S. 1911 Government Model auto pistol magazine, which was altered by the addition of a notched rib down its back to allow for the use of the original SMLE magazine release. The magazine was sleeved to accommodate the more svelte mag. Rubber — and later Bakelite — inserts were fitted to the underside of the bolt handle to reduce noise when the bolt was closed.

Subsequent to the French operation, in late 1944 De Lisle took his carbine to the Ordnance Board, which performed a series of tests where the De Lisles were pitted against silenced STEN submachine guns, silenced U.S. M1 Carbines, and K98k Mauser rifles. The De Lisle bested these arms to a considerable degree in reliability, sound reduction and muzzle flash. Accuracy, too, was acceptable; the .45-caliber carbine provided sub-2-­inch groups at 30 yards.

Surrounding the barrel and silencer components was a phosphate-­finished tubular steel casing, atop which were mounted simple sights consisting of a slightly modified SMLE front with an altered P.14 rifle protector. A V-­notch rear was elevated by a sliding insert.

Of course, the heart of the system was the silencer. Principal parts (see accompanying diagrams) consisted of 13 circular duralumin baffle plates, the 7-­inch Thompson barrel perforated with vents and fitted with an extension nozzle, barrel shield, baffle plate, dual locating rods and outer steel casing, front casing plate and false muzzle.

The circular baffle plates had a hole in the center to permit the bullet to travel through them. They were slotted at the top so the corners could be bent in such a manner that the gasses generated swirl through the length of the casing. As the bullet passed through the barrel, gasses were released through the vents into the expanding chamber around the barrel, building up a back pressure, the expansion nozzle at the barrel muzzle preventing a partial vacuum. When fired, the gas pressure produced in the silencer is higher than the exterior atmosphere. It leaves the tube as a jet of gas moving at a sufficiently low velocity to produce little or no sound.

The front casing plate was secured by a pair of Allen screws, replacing earlier slotted types. Holes were pieced at the bottom of the plate for expulsion of powder residue.

After considerable testing, the De Lisle carbine was declared fit for service. Patents were taken out, and a contract for 500 units was placed with the Sterling Armaments Company, also in Dagenham. The order eventually was reduced to 160, though it is unlikely that, ultimately, no more than 130 were constructed.

The Sterling De Lisle resembled the Ford prototypes to a large degree, and it was constructed out of similar components. Most notably, the sights were changed, involving a Lanchester sub-machinegun-­style rear, which was later modified, somewhat by Sterling with 100- to 600-­yard designations to more appropriate ones at 50, 100, 150 and 200 yards. A simpler, protected, front blade that’s adjustable for windage replaced the original component. Most dramatically, silencer casings were changed from steel to aluminum to save weight. The gun was also fitted with a wooden forend, a feature lacking on the Ford prototypes.

Basic specs were: Barrel length, 71/4 inches; overall length, 353/4 inches; weight, 8 pounds, 4 ounces; caliber, .45 ACP; magazine capacity, seven. It was handy, rugged and reasonably well-­balanced. The report produced was measured at around 85.5 decibels.

Butt socket markings of the original converted condemned Mark IIIs were retained on the De Lisles and reflect several different origins, including at least one from Ishapore Rifle Factory in India.

During development it was thought an airborne version of the De Lisle with a folding stock might also be a good idea, and a pair was constructed and fitted with Sterling-­style folding SMG stocks. The concept was found lacking, and the project was scrapped early in the development phase.

Though small in numbers, De Lisles saw considerable dispersal. They were principally used by Commandos during World War II for special operations in Europe. They also saw employment in Burma, and later in the Korean War and Malaya, as well as likely in Northern Ireland. Original De Lisles are exceedingly rare with few examples extant.

Fortunately, for suppressor and World War buffs, scarcity no longer has to be a problem. As noted, U.S. Armament Manufacturing is purveying a faithful reproduction of the period De Lisle. The project is a worthy follow-­on to the firm’s heretofore highly successful reproductions of .45-­70 Bulldog Gatling Guns and the Colt Model 1903 pocket auto.

Using the same internals as the original, and like some constructed out of Ishapore No. 1, Mk III SMLES, the new guns offer today’s shooter the opportunity to experience the same qualities that made the gun such a sought-­after piece of Commando hardware.

To ease the transfer, and for production and cost reasons, there are a few differences not obviously apparent cosmetically nor affecting the 1940s product’s performance. Some minor modifications were deemed prudent to make the U.S. Armament Commando carbine. Most notably, these involve reinstating the steel silencer casing of the Ford Prototype models for durability, using actual SMLE rear sights in favor of a Lanchester style, and welding the 7-­inch barrel to the casing so that it meets a legal 19-­inch length, thus eliminating the need for an additional short barrel rifle (SBR) tax stamp.

Of course, most markings are also different, primarily those reflecting the address of the current manufacturer. The stock sockets do retain the “ISMLE” Ishapore stamping. Too, it was found that it really was not necessary to recess the bolt head, as rounds performed just fine with the original smooth configuration and using the existing extractor. As later Ishapores — ones used in the construction of the Commando — were not made with brass butt ID discs, new ones were not added.

Like all U.S. Armament projects, great attention was placed on detail and quality. The guns are hefty pieces, weighing in at 91/2 pounds, however, they are eminently shoulder-­able, and, as one might expect, recoil with the .45 ACP is virtually nil. Finish is Parkerizing; handguard and buttstock are walnut. Overall length measured 36 inches. Magazine capacity is seven rounds.

In G&A’s evaluations, using 230-­grain Winchester and Federal .45 ACP FMJs, firing the guns at an Ordnance trials range of 30 yards with out-­of-­the-­box sights, both brands of ammo were able to produce consistent sub-2-­inch groups, slightly low and to the right of point of aim, the latter being eminently correctible by simply adjusting the sights using the moveable rear notch and front sight blade.

The provided altered 1911 magazine fit easily and securely in its modified mag well, and feeding was quite good once we got used to the feel of the shorter throw of the attenuated Enfield bolt. Outdoors — sans ear protection — the De Lisle carbine proved to be one of the most silent suppressed guns I have ever fired. Indoors — and wearing muffs — the report was more distinctly heard, but still not anywhere near what one would experience with an un-­suppressed Thompson or Government Model auto.

In the company’s inimitable style, once again U.S. Armament came up with an intriguing, evocative piece of history that can be enjoyed by 21st-century shooters. The price of the Commando carbine is $6,499. To learn more about acquiring one, contact U.S. Armament Mfg. by visiting their website or calling 717-721-­4570. 

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