DeLisle Silenced Carbine

Article written by F. A. Mancuso, weapon from the Museum of Modern Guns, Repubblica di San Marino

Is this the right place to talk of this special purpose weapon?

While on these pages there is room for every individual gun that wore an uniform, I am not quite sure that all these nice carbines had dismissed their ones, and that they are still on duty somewhere in the world, instead.

It is not by mistake if I am saying "carbines" instead of "carbine", as we will see later on, but let's start from the beginning.

The defeat at Dunkerque lowered severely the morale in UK: Winston Churchill was aware that it was not possible to launch any major military attack on the Germans, so he ordered the creation of a raiding unit that was in charge to land, usually at night, in the Western Europe occupied by the German forces, to destroy specific targets and quickly leave, using hit-and-run tactics, to make the occupants fighting an enemy they could not see.

The idea was that the operations carried out by this unit would have been a great help for morale: he said that "There ought to be at least 20,000 Storm Troops or 'Leopards' drawn from existing units, ready to spring at the throats of any small landings or descents."

Lieutenant-Colonel Dudley Clark of the Royal Artillery proposed for the new force the name "commando": this term, used in the Boer War, was approved by Winston Churchill but not generally appreciated by the military hierachies that preferred to refer to the new force as Special Service. [1]

Recruits were initially drawn from the British Army, selection for the new commando force was necessarily demanding and Churchill himself ordered that those men should be equipped with the best equipment.

And the creation of Mr. William Godfray DeLisle has had the right to be among the above equipments, as it was as efficient as possible, accurate, lethal, silent, compact, and would kill a man well beyond the range of a knife.

The ingredients of this recipe are:
- a standard Enfield action with a shortened bolt; 
- a 45 ACP chambered barrel, reamed to fully support the case; 
- a pistol magazine, fitted with a brazed lug to engage the Enfield magazine catch, and a sturdy magazine housing; 
- a high volume silencer where a spiral diffuser system follows an expansion chamber.

The noises that come from shooting a gun are due, for the most, to the gun mechanism, to the expansion of the gas, to the movement of the bullet in the air.

The utilization of a bolt action solved the first problem, and plastic inserts put, in the later models, where metal surface met silenced not only the clatter of the bolt but also the criticisms from weapon's detractors, while the subsonic cartridge (already in use with the Thpmpson 1928A1 by the British armed forces) avoided the shock wave that follows a supersonic bullet.

The silencer is the core of the gun.

As a rough description (a more detailed one is available inside the patent specification) we have a tubular casing (14) that is mounted eccentrically on the barrel (12), the rear constitutes the expansion chamber (16), while the portion that extends in front of the muzzle constitutes the baffle chamber (18).
A cilyndrical shield (66) surrounds the front end of the barrel and form an annular space (68), open at rear end, that is connected with the interior of the barrel by means of some vents (70) evenly spaced around the periphery of the barrel.
The muzzle ends into an expansion nozzle (62).
A set of evenly spaced baffle-plates (50), supported by two rods (only nr. 40 can be seen in the picture) that run parallel to the barrel, provides a spiral passage to the gas escaping from the muzzle of the barrel.

As the bullet starts to move, the column of air inside the barrel is pushed towards the muzzle and create a back pressure in front of the nozzle. As the vents of the barrel are uncovered, gas escapes from the vents and the above back pressure builds up. This helps the nozzle to prevent a vacuum from being formed at the muzzle, and the subsequent noise of the implosion. The shield prevents the gas escaping through the vents from impinging directly the wall of the casing, which would be another source of noise.
As the bullet travels through the baffle-plates, the column of gas that is behind it strikes the baffle: as the path of the bullet is off-set from the axis of the baffles, the gas are forced to swirl so that the vortex is central with the casing, greatly reducing its velocity. Each baffle deflect only a portion of the total column of gas, that is why a set of baffles is needed.

Someone says that basically it is an enlarged version of the Maxim design, and that the effectiveness of the carbine is only due to the big volume of the casing; in any case, the noise made when shooting the gun has been described as "the sound of a book dropping from your desk to the floor".

Now, let's have a look at this sample, but, first of all, readers should be warned that it not a completely original firearm: the casing of the suppressor was badly damaged when arrived at the Museum, so its owner had to restore it.

It is known that there are a lot of variation among these carbines, as they were tailored according the requirements of the "end users"; this case is not an exception to the rule.

The action does not came from a No.1 rifle, but from a No.4, so this should not be one of those produced by Ford Dagenham of London, or by Sterling  Engineering Co. during the II World War; the lack of any kind of marking does not help in identifying its origin.

Here below the right side...

... then the left side, where there is the spring loaded ejector, that is necessary as 45 ACP cases have a rim that are smaller than the 303 British ones...

... and a top view, where we can see the rear end of the barrel, the ramp, the typical 1911A1 magazine follower, the bolt head, and the bolt body. Note that the front end of the lightening slot milled in the reinforcing rib: it seems that this bolt has been made short from the beginning, and that it was not made by shortening an original No.4 bolt.

The charger bridge and its brackets have been removed.

The backsight assembly, of the milled type, is quite unique, and is worth of a close examination.

The battle sight aperture is fixed to the slide, it is not fixed at the rear of the leaf.
While the slide is raising, it is also moving to the left, to compensate the lateral deviation of the rainbow-like trajectory.

There is also a windage adjustement screw: and this is necessary, as only the front sight is mounted on the casing.

The leaf is graduated from 10 to 260 yards on the front side, and from 0 to 64 mils on the left side (it could be useful to made corrections, if you can evaluate them, in case of major angle of sight).

In the end, the front sight.

The first 17 handmade prototypes were put in use immediately in the occupied France: then other successful operations were carried out behind the lines in France, in Holland, in Germany. After the D Day there were only a few operation for which the DeLisle was suited in Europe. Several carbines were sent to the Far East, to fight against the Japanese. After the II WW, it was used in Korea and Malaya.

Someone says that it was on duty at the end of the 1960's against IRA, and in service again for the Falkland / Malvinas War, even if at the date the carbine should have been replaced by the Sterling Patchett Mk5 (or L34A1).

But it is believed that the production and distribution of the carbine was a lot more widespread than has been previously reported, as it seems that several countries made copies of the DeLisle.

The carbine was a private venture, but the monetary profit for William De Lisle was very limited, as he received only the royalty payments of three shilling for each of the 500 carbines commissioned to Sterling Engineering Co. (actually only about 130 were made): his real profit was the satisfaction of contributing to the war effort.

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[1] The following excerpt from "The Boer War" by Thomas Pakenham, 1979, can better explain the meaning of the term "commando" (and, possibly, why, in 1940, the British military hierarchies preferred to use a different one):
"Their elected civilian leaders were made commandants - appointed, that is, to lead the five hundreds or two thousands burghers of each commando in battle. In this commando system it was no one's job to train the burghers. Apart from the annual wappenschauw (or shooting practice), the men were left to fight as they had always fought - with the tactics of the mounted frontiersman. If the enemy were superior in numbers, they would provoke the enemy's attack, dismount, take cover and shoot, remonut and ride away. In European military manuals it was a formula known as 'strategic offensive, tactical defensive'. The Boers had never seen the manuals. But the tactics had served them well in countless wars against natives - and in 1881 at Laing's Nek against the British.

Bibliography

* I. D. Skennerton - The Lee-Enfield - 2007, Ian Skennerton Publishing
* R. T. Rome - WWII Silent Killer Still Lives: the death-delivering DeLisle - GUNG HO, June 1984
* J. Minnery - The Commando Carbine - PMA
* G. Marino - Il grande libro dei silenziatori - Giovanni De Vecchi Editore, 1985
 

Internet

* http://www.prexis.com/sten/homebuilder/index.php?referredby=1 an interesting forum, expecially for craftmens!