This section details some Service arms adapters and conversion units for training.
The units dealt with on this page are those which will fit to the parent full-bore arm allowing temporary use with sub-calibre "miniature" cartridges. Other systems have page links.
There are also two most interesting extracts, taken from old publications, relating details of such equipment . One is dated early in the Twentieth Century, and the other in the 1960s
The Morris and .22RF Aiming Tubes
and the German K98 .22RF conversion unit
The ".303 cum .22" conveyor system
plus The Williams Floating Chamber
See also other Sub-calibre systems plus Sub-target_devices
For some unusual non-training Enfield rifle adaptations, see: Enfield Service rifle accessories and adaptations
View also Miniature Calibre Ammunition
and a: Chronology of Enfield genre Training Rifles, Adapters & Cartridges
The War Department's " List of Changes in British War Material" (LoC - 4452) show the date of approval for introduction of the first aiming tube - for the Martini Henry .577/450 rifle - as 14th. November 1883. The patent for the devive had been applied for by the inventor, Richard Morris, on the 25th. of April 1881; application no. 1773.
The equipment was officially described as " Tube, Aiming, Morris's, Martini-Henry Rifle, (Mark I) "
That for the carbine came just over two years later.
There are advertisements and references to be found for the use of the Morris Tube in the Snider conversions ( the first British breech-loading service rifle to be introduced) of the Pattern '53 (1853) Enfield rifled musket, itself the first generally issued rifled (muzzle-loading)British service long-arm.
When the Martini-Henry rifles were converted to .303CF (Centre Fire), initially with Metford rifled barrels and latterly with Enfield rifling, aiming tubes were introduced for the adaption of those full-bore rifles to the Morris .297/230 miniature cartridge for training purposes. These tubes were necessarily thin-walled compared with the original aiming tube for the .450 Henry barrel.
The carbine's final conversion markings of "MT" on the knox-form
and on the RHS of the butt stock are illustrated below.
The rifle shown is chambered for the Long cartridge. The flanged sliding extractor of the Morris chamber is pulled back by the original full-bore extractor as if it were a .303" cartridge.
See more on the Martini Metford MT carbine and the Morris Aiming Tube
The use of these "Morris tubes" was continued when the bolt-action Lee-Metford and subsequently Lee-Enfield rifles were brought into service. The first such aiming tube was introduced for the "Long" Lee-Metford late in 1891.
The "Morris Patent Tube Company" as well as manufacturing the aiming tubes and ammunition, are today less known for their marketing, around the start of the twentieth century, of an associated target system - the Morris Patent target. This device was a vertically orientated target box of several feet in height. The patented TARGETS fitted within and were printed vertically onto a tall sheet to represent ranges from 100 yards at the bottom to 800 yards at the top, with a circular aiming or zeroing black mark at the very base. Targets were available for an amazing number of short ranges - for 5, 10, 15 and 25 yards and this with a 40-odd grain bullet in a blackpowder centre-fire cartridge. Whether the target arrangement was still either present or visible, after a good number of rounds had been fired, is a matter for conjecture! Indoor use would be interesting to say the least!
See also: Miniature Calibre Cartridges
THE .22RF (Rim-fire) AIMING TUBE
With the demise of the Morris cartridge, aiming tubes were introduced in .22 Rimfire calibre for the .303inch calibre centre-fire Service rifles. The equipment, housed in its wooden box, consisted of the tube, with its chamber and extraction sleeve attached, a bolt fitted with a modified bolt-head and a cleaning rod with .22 jag. See also pages for the Long-Lee .22RF conversion and the SMLE Mk.III* fitted with an aiming tube.
The bolt has been removed from its resting place at the left hand end of the box
Image courtesy of the Trustees of the Imperial War Museum - London
Below is an advertisement for the Morris and Aiming Tubes from the 1935 A.G. Parker catalogue
Notes on the MORRIS SYSTEM and other SUB-CALIBRE devices - from THE CITIZEN RIFLEMAN - 1906 - by E.J.D. Newitt
REDUCING DEVICES FOR ENABLING THE USE OF LOW- POWER CARTRIDGES
IN MILITARY RIFLES
Innumerable attempts, attended with more or less success, have been made to fire low-power cartridges from high-power rifles, but up to the present no device
is yet obtainable which realises the minimum in the matter of power and cost, nor the maximum of accuracy. Reduction is accomplished in two ways : By reducing
the calibre by the insertion of a smaller calibre barrel inside, the other, and by reducing the charge, the calibre remaining the same. The Morris aiming tube is an example of the former method. It has been extensively used for the past quarter of a century in guns, rifles, and artillery. A rifled barrel of .23 calibre, with a breech of .297 calibre, is inserted in the rifle from the breech end and secured by a washer and nut screwed upon the end projecting from the muzzle.
The 297.230, or Morris cartridge, is made of two powers, the long having a charge of 5 grains of gunpowder or its equivalent in nitro explosive, and a bullet weighing 38 grains—the short having 3 grains of powder and a bullet of the same weight, both with central ignition. The former cost about £1, and the latter £1:2s:6d ( £1.175)per thousand.
The energy generated by these cartridges is considerable, and in point of accuracy they leave room for improvement. The exterior dimensions of the tube are limited by the calibre of the barrel in which it is used. In the case of the British Service weapon this is .303. The calibre of tube being .23 it cannot exceed .0365 in
thickness, and must therefore be very delicately handled. Where a large amount of shooting is done from a few tubes, as will usually be the case, tendency to lead and foul necessitates frequent wiping out. Thorough cleaning at the close of shooting is best done with the tube in the rifle, but it must be frequently removed to allow of the rifle's own barrel and chamber being cleaned. The use of any reduced cartridges usually requires an alteration of the rifle sights, which, being normally
attached to compensate the jump of the barrel caused by the full-power charge, require readjustment when the jump is altered by smaller charges. The adoption of a backsight permitting lateral adjustment, the issue of which for all rifles used in the British service has been officially announced, will minimise the difficulty of readjusting the tube after removal, to shoot accurately to the sights, so far as lateral deviation is concerned, but a higher foresight may still be required.
As its name implies, the Morris aiming tube is designed to test the accuracy of the user's aim whilst receiving instruction with the Service rifle. This it accomplishes within its own limit of accuracy, and as an auxiliary to the Service rifle it is invaluable. Considered solely as a rifle for Club purposes it involves the purchase of an expensive rifle, comparatively expensive ammunition, of insufficient accuracy. On the other hand it possesses the advantage of enabling practice with the war weapon at short ranges, and by removing the tube the rifle may be used with its full charge. Several low-power cartridges with projectiles of the same calibre as the rifle barrel have been designed, but the difficulty of adapting a cartridge of this kind to a high-power rifle cannot be said to have been at all satisfactorily solved.
The calibre prevents the reduction of the weight of the projectile beyond a certain minimum, which is such as to demand a commensurate explosive charge for pro pelling it at the lowest speed consistent with accuracy, and consequently a sufficient reduction of power is only secured at a sacrifice of this essential feature.
The sharp pitch or twist of the rifling of the Service arm is entirely unsuited to a short and soft lead projectile, and frequent cleaning is necessary to mitigate the
consequence of " leading." Several of these require the use of a bush or breech adapter for reducing the area of the chamber, and which seldom secure complete obturation of the breech. Cordite is the explosive employed, and great care is necessary in cleaning both the rifle and adapter after use. These cartridges have central fire ignition, and cost from 45 shillings to 50shillings (£2.00 to £2.50) per thousand.
Another reduced charge cartridge which can be used without a breech adapter and fed from the magazine, is known by the name of its inventor, Major Gaudet. The base of the projectile is protected by a hard metal cap which takes the rifling fairly well, and minimises leading. The lowest power is capable of considerable accuracy up to 25 yards. For shooting beyond this distance higher power is required, and the energy generated exceeds the limit of power with which this work is concerned. The price of Gaudet cartridges is 45/6 (£2.275) per 100.
The " Trask " ammunition involves the use of a steel adapter and a composite cartridge, the hard metal-capped bullet being inserted in the mouth of the adapter and the cartridge containing a smokeless powder charge, in the base. Their cost is 40s. (£2.00) per 1000, and the steel adapters 6d. each.
OTHER SUB-CALIBRE DEVICES - The KYNOCH and RECORD adapters, plus the ".303 cum .22" system
The "KYNOCH" ADAPTER
The adapter is in the form of a sleeve (A), in the nature of a .303in cartridge case. the small slot in the rim of the adapter is lined up with the gas vent on the LHS of the action body reinforce, through which a sprung split-pin (C) is passed to prevent the sleeve from rotating. The larger gap in the rim permits the extractor (F) to freely pass over the rim (D) of the miniature cartridge (B) and pull the fired case clear of the chamber without also withdrawing the adapter sleeve.
The lever tool (E) is solely for removal of the adapter after use, and, of course, after removal of the locating split-pin.
A.G. Parker marketed a "home" sub-calibre unit for the Service rifle. Produced by "Record" - possibly the famous workshop machine-vice manufacturer - this device fired bulleted-breech BB) like cartridges. Being an adapter which fired a smaller calibre bullet than the bore of the parent arm, accuracy must have been limited even at the quite short indoor ranges at which it was intended for use; indeed, rather akin to the .303 cum. 22 system when fired in the Vickers machine gun where, unlike the use of the conveyor in a purpose converted, .22RF barrelled, S.M.L.E. rifle ( see the Pattern 18 Lee-Enfield ), the .22RF bullet was propelled down the .303" machine gun barrel and used at a range of, usually, only twelve yards. In this guise, the conveyor system was obviously not automatic, and intended only for basic training and aiming practice.
The Record system was really only a " plinking" device, but certainly offered an opportunity to keep your hand in at home, especially for off-hand practice, as long as a safe place of use could be found! The plates on the Welsh dresser could certainly then be at risk if the system was used in the warm kitchen on a cold Winter's eve, possibly as much because of the accuracy of the set-up as any inadequacy in the shooter!
See also the A.G. Parker ".303 cum .22" conveyor system mentioned above and illustrated immediately below.
A later, and considerably more sophisticated, adaptation for a Service rifle was the Mauser based design for a .22RF conversion unit - patented in 1935 - for the K98 rifle most commonly in use with the German forces. This unit comprised of a complete, one piece, insert for the barrel and receiver. The new receiver obviously had its own purpose-built bolt, unlike many other equivalent conversions which modified the bolt-head of the parent arm.
The unit bears more than a passing resemblance to action of the Mauser KKW (Klein Kaliber Wehrsportgewehr), but more particularly that of their .22RF calibre "DSM 34" (Deutsches Sport Modell) training rifles, manufactured by Mauser and several other arms companies, such as Erma and Geco, between the wars (WWI and WWII) and subsequently during WWII, for training recruits, the cadet units and the more familiarly known "Hitler Youth".
Such a conversion unit, held at the Imperial War Museum, is illustrated below. This particular example is manufactured by Haenel Waffen-u. Fahrradfabrik, Suhl.
Images of the K98 conversion unit by courtesy of the Trustees of the Imperial War Museum - London
This equipment consists of the barrel and action assembly, including the bolt, along with two magazines (one missing ) and a replacement for the parent arm's magazine base-plate. This new plate has an integral magazine slide to accommodate the sub-calibre magazine. The small bar with a knurled handle, resting in a slot to the right of the bolt-handle, is a "tommy bar" that fits the locking nuts which clamp the conversion unit into the action of the parent arm.
shown in position below
The "large "O" marking on the magazine base-plate indicates that the unit was issued for Naval use.
Left: the replacement base plate.........................................................................Right: the .22 magazine
This particular unit is not strictly under the remit of these pages, not being a rifle adapter, but it is a remarkable design and worthy of mention - and is believed to have also been used for training on sub-machine weaponry.
The clever concept permitted semi-automatic use of a sub-calibre round in a full-bore pistol, carbine or rifle. The sliding chamber section imparted energy, acquired from the recoil of the firing of the under full-size round, to action the weapon - at the same time generating a sensation, for the shooter, more akin to that of a larger calibre round being fired.
This particular unit is not strictly under the remit of these pages, not being a rifle adapter, but it is a remarkable design and worthy of mention - and is is also believed later used for training on sub-machine weaponry and certainly on the Browning Machine Gun.
The floating chamber principle, was the invention of Marshall Williams, who devised it whilst serving a sentence in a United States penitentiary for an offence committed during the days of Prohibition.
Below is a facsimile of the brochure advertising the .22" Colt Ace pistol. The system was more usually sold as a conversion (adapter) unit for the Colt 1911 .455 or .45 Automatic. This adapter was probably the most common usage of the Williams floating chamber.
Two types of conversion specifically referred to in the text of the following excerpt are:
Alongside the development of the ·22 rifle
and its ammunition there have been inventions, some excellent, some useful,
some downright impractical, relating to the · 22 as a training arm,
as an ancillary weapon, or as an accessory to it. Two remarkable developments
standout: one perfected in the United States and one in Great Britain. The
first, the floating chamber principle, was the invention of Marshall Williams,
who devised it whilst serving a sentence in a United States penitentiary for
an offence during the days of Prohibition. For sometime the American forces
had been using the Colt ·45 semi-automatic pistol for training their
personnel, but the cost of ammunition presented problems. The use of a ·22
pistol, built like the ·45, did not solve the problem. Smaller calibre
ammunition made it more economic but without the buck of a heavy pistol in
recoil, the use of a ·22 did not assist much in preparing a nervous
recruit to handle the heavier handgun. Williams devised the floating
chamber in which the gas produced from the fired cartridge of a ·22
was allowed to escape at the front of the chamber. This gas thrust against
the area of the cartridge base plus the considerably larger area of the chamber
front. The backward action of the gases was therefore considerably increased,
the thrust of the weapon in recoil greater in consequence. The net result
was that a ·22 pistol was built giving the same recoil as the larger
The next step was the incorporation of the floating chamber using the ·22 long rifle cartridge into the Browning machine-gun. In addition to building floating ·22 chambers for many semi-automatic rifles, Williams designed the short-stroke piston for the Garand automatic carbine, but that is outside the scope of a brief historical survey of the ·22.
Improvements have been made on the original Morris tube invention - ·22-calibre adapters have been made to insert into the barrels of shotguns, whilst Parker-Hale Ltd of Birmingham brought out a really first-class adapter for the Webley and Scott ·455 calibre service revolver. This, though it did not incorporate any floating chamber principle to increase recoil, was none the less a great aid in training the pistolmen in shooting. It was made in two patterns, as a single-shot adapter, in which the cylinder was removed from the pistol so that it was fired in skeleton form, or complete with a special cylinder chambered for the ·22 rim-fire cartridge. This adapter was also manufactured for the ·38-calibre Enfield Service Revolver
These adapters are still in use today and used fairly extensively. They do not affect the accuracy of the revolvers and are guaranteed to shoot into a 3/4 - inch group at 20 yards, which is better than the handler can claim.
The most remarkable development was, however, the principle, derived from the Morris Tube, by Mr. A. T. C. Hale in introducing the system which he called 'Parker-rifling'. In this, worn barrels are bored out and a new rifled tube is inserted. Nor is this confined to worn barrels, for many larger bores, such as ·303 service rifles, can be converted to ·22 rifles by this process. It is an economical way of making a first-class sporting arm from an obsolete military one. It is not suitable for military cartridges, nor for high-power sporting cartridges, though Parker-rifling is suitable for the ·22 Hornet. It seems strange that many a useless high-power, large-calibre weapon should become a small ·22-calibre arm capable of extremely accurate shooting, yet there it is. Commonplace the ·22 may be, yet its history is colourful and proud: whatever the future may hold in the development of firearms and ammunition, the little ·22 occupies an important position in the history of firearms as a whole. Large-bore riflemen may hold it in contempt, but most successful riflemen start with this weapon, while for military purposes its utility in training has been proved time and time again.
From the standpoint of the ordinary shooter, the ·22-calibre rifle is the most important in the world and there is a lot to be said for their attitude. Perhaps, speaking of Great Britain alone with its growing numbers of riflemen, one could parody the old song and say: 'Four thousand rifle clubs can't be wrong!'
Richard Arnold could hardly have foreseen the change in climate that would take place only thirty-five years after he wrote this piece in 1962.
For the lesser known sub-calibre equipment used with the Second World War British Anti-Tank rifle designed at the Royal Small Arms Factory, Enfield, see
The "Boys" (Stanchion) Anti-Tank Rifle
For later examples of .22RF Conversions and adapter units see
The FN Self Loading Rifle L1A1 and L12A1 conversion unit
The Enfield Cadet Rifle L98A1
For some unusual non-training Enfield rifle adaptations, see:
Enfield Service rifle accessories and adaptations
See also: Miniature Calibre Cartridges
and a: Chronology of Enfield genre Training Rifles, Adapters & Cartridges