Last week Matt attended SHOT Show 2020 and spotted a pair of Tavor cutaway demonstration guns at the IWI booth. Above is a quick video, put together on the fly, looking at the cutaway guns and showing how they illustrate the Tavor’s working parts and operation.
Developed in the mid-1990s to meet IDF requirements for a reliable and compact rifle to replace the M16s & M4s in service. The rifle had to be shorter to deal with the close quarter urban fighting the IDF often found itself in.
The Tavor or TAR-21 uses a long strike gas piston system inspired by the AK and has a rotating bolt. The bullpup configuration gave the desired compact weapon without sacrificing barrel length.
The cutaway rifles on display at the IWI booth were actually civilian, semi-auto only, Tavor SARs but they give us a good look at the rifle’s internals and how the Tavor functions. We can see the gas piston system, the charging rod and the barrel at the bottom. Moving back we can see the chamber, the bolt carrier group, the sear assembly and the bolt hold open mechanism.
They also cutaway the magazine so we can see the spring inside. At the top of the weapon we can see the mainspring that stretches back into the butt. The model was fully functional so on pulling the trigger the connecting rod acted on the sear release to trip the firing pin.
Additionally, the bolt release, just behind the magazine, also functioned and when operated the bolt went forward onto battery. The Tavor entered service in the early 2000s and has been superseded by the X95 and joined by the 7.62 chambered Tavor 7.
We will have a more in-depth video on the Tavor in the future.
Commonly referred to as Nock Guns, the seven barrel volley guns were actually designed by James Wilson. Wilson presented his design to the Board of Ordnance for testing in July 1779. Following testing at Woolwich Arsenal the Board of Ordnance decided that the guns, while of no use to the Army, might be useful aboard the Royal Navy’s ships. The volley gun’s impressive firepower could be devastating at the relatively short ranges aboard ships. The Navy had historically used blunderbusses/musketoons and the Board of Ordnance probably viewed Wilson’s gun as an advancement of this concept. London gunmaker Henry Nock was given an order for two ‘seven barrelled rifle guns’ for Admiralty testing but these proved slow to load in action and subsequent guns had smoothbore barrels.
The Admiralty envisioned equipping first rate ships of the line (vessels with 75 guns or more) with 20 volley guns, while second and third rates would have 16 and 12 volley guns respectively, and frigates would carry 10 Nock guns. This represented a sizeable order. The Admiralty eventually purchased 500 guns, paying £13 per gun, to equip Royal Marines and sailors manning the fighting tops (at the top of ship’s masts). The Navy felt that the volley guns’ firepower would be useful when boarding enemy vessels or in repelling boarders by pouring down fire on enemy boarding parties.
Henry Nock, better known for producing high quality duelling pistols and sporting guns, became the sole supplier of Wilson’s volley guns to the Royal Navy. The weapon’s 0.46 inch calibre outer barrels were arranged around the seventh centre barrel. The 51cm or 20in barrels were brazed together and screwed to an iron plate set into a walnut stock. The outer barrels had vents drilled through them to the central barrel while the central barrel had a vent leading from the lock. Once the flintlock ignited the powder charge in the central barrel, the surrounding barrels were ignited through the vents. As the vents had to be drilled with the barrels already brazed into position, the outer barrels all have plugged drill holes on their outer surfaces.
All seven barrels fired almost at once producing significant recoil, reputedly able to dislocate shoulders. The service load was originally 2.5 drams of finer rifle powder (which I believe equals 68gr) for each barrel – totalling 476gr. Despite the gun weighing 12lbs, this did little to mitigate the weapon’s recoil and a reduced charge or 1.5 drams of standard musket powder was ordered.
The Board of Ordnance and the Admiralty granted Wilson an awarded of £400 (equal to £48,000 or $63,000 today) in May 1780. He played no further role in the testing and development of the volley gun. In 1787 the Navy ordered a further 100 guns from Nock.
Entering service just too late for service during the American War of Independence the first reported use of the guns came with Admiral Howe’s fleet at the siege of Gibraltar in 1782. They continued to be carried aboard other vessels during the 1790s, but few accounts refer to them and little is known about their service.
Howard Blackmore suggests that naval officers, including Admiral Nelson who disliked placing marksmen in his tops, disliked the guns. There were some fears that the volley guns’ wads could set the ships sails and rigging on fire. Reputedly it was also not uncommon for some of the volley gun’s barrels to fail to ignite. As a result the guns were seldom used on board ships and removed from Royal Navy service in 1804. In 1805, Wilson, then a captain of the Marines suggested the Navy reissue the guns to the Sea Fencibles, a naval militia which helped defend the British coast, however, his recommendation was not followed up.
This particular example has the second pattern of lock used on the Nock guns with a smaller lock positioned a little lower on the gun. The earlier pattern was a back action lock, fitted high on the gun with the front of the lock plate in line with the side of the barrel.
The gun has a maker’s mark of ‘H. NOCK’ on the second barrel on the left and various barrel proof marks. Unlike other examples the lock itself isn’t Tower and ‘GR’/Crown cypher marked but does have the Ordnance Broad Arrow just behind the pan. Interestingly, the steel ramrod appears to have an extension brazed onto the end of it, this might indicate that the shorter rod used with the initial charge had to be extended when less powder was used for the lighter 1.5 dram load.
Why did the Nock Volley Guns fall out of favour?
As I mentioned earlier the recoil of the initial service load was significant, Howard Blackmore hypothesised that there may have also been some weakness to the lock springs leading to misfires. One key factor is that close quarters fighting aboard ships often relied on edged weapons like cutlasses, boarding axes and pikes. These paintings give us some feel for what fighting aboard a Napoleonic Man-of-War might have been like – a close, chaotic, terrifying affair.
While pistols were commonly used they were disposable and may not have been reloaded during a fight – more likely they were dropped or used as a club. The Nock Gun would have offered a devastating first volley, and while its 20 inch barrels would have given it better accuracy and range than a musketoon, how much of an impact a single volley of seven .32 bore projectiles would have had especially once the fighting became hand to hand is a matter for debate. At close quarters the Nock Gun quickly becomes a short, ill-balanced, 12lb club.
The Nock Volley Gun is perhaps best known for appearing in the Sharpe series of books and films as Sergeant Harper’s weapon of choice but it first appears on screen in the 1960 classic The Alamo with Richard Widmark’s Jim Bowie carrying one and more recently a fleeting, anachronistic, appearance in Master & Commander: Far Side of the World.
Despite a relatively short and undistinguished service life the Nock Volley Guns also saw some civilian sales with a number of ornate hunting guns with wooden forends, engraving, rifling and rear leaf sights.
Later in 1818, Nock’s workshop manufactured a design by Artemus Wheeler, an American gun designer with a fondness for revolving guns.
Wheeler’s carbine resembles the earlier volley gun externally but is in fact a manually rotated, self-priming flintlock ‘pepperbox gun’ with six barrels arranged around a central axis. Unlike the earlier volley gun the pepperbox carbine was never trailed or purchased by the Admiralty. Henry Nock’s workshops produced approximately 655 volley guns between 1780 and 1788. The Nock Gun is a weapon that would greatly benefit from some in-depth contemporary research as the current best source is over 50 years old and relatively little is known about the gun’s service history.
Today, we’re going to take a look at a little known type of weapon which rose to prominence in around the time of the First World War with a number of examples being developed and some even tested. As you can see from this footage it’s something pretty unconventional, seen here mounted on the back of a truck – is a centrifugal machine gun.
I found this short footage while doing some digging through the online catalogue of the US National Archives. The centrifugal machine gun was not a new concept by the time this footage was filmed in the early 1920s, sadly the footage notes done give an exact date.
A still from footage of the demonstration (US National Archives)
While the technology had risen to a new prominence what was the allure of centrifugal machine guns? The principle of centrifugal force – an inertial force which appears to act on objects moving in a circular path, directs them away from the axis of rotation. As a result a centrifugal machine gun required no propellant powder to propel the projectile, or a case to contain it, nor a conventional rifled barrel to stabilise the projectile. Once released from the axis of rotation the projectile travels on a linear trajectory until it expends its energy. It works along the same principle as a primitive sling. The primary issue is providing power to exert the centrifugal force and a means of accurately firing the projectiles.
Some of the earliest work on centrifugal guns was done in the late 1850s in the US. The hand-crank or steam powered guns patented by William Joslin (US #24,031), C.B. Thayer patent for a ‘machine gun’ in August 1858 (US #21,109) and Charles S. Dickinson (US# 24,997) in 1859. Dickinson went on to secure financial backing from a wealthy Maryland industrialist Ross Winans and developed a steam powered version of his gun. Despite gaining much press attention Dickinson’s centrifugal gun saw no action during the US Civil War. In 1862 G.C. Eaton and S.W. Turner also patented a ‘machine gun’ (US #37,159).
An illustration of the Winans Steam Gun, Frank Leslie’s Illustrated Newspaper, May 1861
It wasn’t until World War One that the concept began to be considered again. In June 1918, Major Edward T. Moore and Saul Singer filed a patent for a centrifugal machine gun powered by an electrical motor (US #1,332,992). The motor spooled up the centrifugal barrel assembly to rotate extremely quickly and impart centrifugal force on projectiles. According to Julian Hatcher the gun could fire steel ball bearing projectiles at approximately 1,200 feet per second. Fire was controlled by a stop pin in the ammunition feed tube. Moore claimed the weapon could fire a projectile 1.5 miles with enough force to kill a man. He also suggested the weapon’s rate of fire approached 2,000 rounds per minute. It appears that Moore’s gun may have been tested in 1918 but Hatcher described its accuracy as ‘extremely poor’.
Photograph of Moore’s gun during testing (Hatcher)
Another centrifugal design developed during World War One was E.L. Rice’s half-inch centrifugal gun, sadly I’ve been unable to find any photographs or drawings of Rice’s design but the weapon was submitted to the US National Research Council in 1917. The NRC’s 1919 report states that the gun had been further developed by the NRC’s Physics Division in Pittsburgh but work had been slowed by “a common defect which has been difficult to eliminate”. Despite what the report described as ‘considerable headway’ the weapon was subsequently abandoned amid some controversy about credit for the design.
There seems to have been something of a centrifugal machine gun craze with several more patents filed between 1917 and 1926. A Scientific American article from March 1918, even noted that “every so often the daily press becomes enthused over a new centrifugal gun.”
One of the earliest patents granted appear to have been for a design by E.E. Porter, granted in January 1917. This was followed in July 1919 by inventor, Herbert A. Bullard being granted a patent (US #1,311,492) on a design which fired a disc rather than a ball. At the same time T.A. Gannoe was granted a patent (US #1,309,129) for a large, complex looking gun shown mounted on a pedestal.
In 1920, F.R. Barnes (US #1,327,518) and W.W. Case (US #1,357,028) were also granted patents which had been filed in 1917. In late 1921, Levi Lombard was granted a patent he had filed in March 1918, his gun even appeared in Scientific American. It appears to be notably smaller than Moore’s gun and has a spade grip for aiming. This was followed in 1923, by an interesting patent from Joseph T. McNaier for a centrifugal gun that could be powered by an electric or petrol engine, some of the patent diagrams show how the gun might be placed in an armoured car or aeroplane (US #1,472,080). Intriguingly, McNaier and Moore appear to have known each other quite well and were partners in a law firm together.
Here’s a gallery of some of the various patents mentioned above, not all are as detailed or as advanced as others:
The question is which of these guns is featured in the footage. The most likely bets are the Moore or the Czegka. Sadly, with only a side view and just 18 seconds of footage we don’t have much to go on. The accompanying reel notes, describing what is seen in each section of the film, describes the gun as being in the “experimental stages only” and that the prototype seen here “is intended for use as aircraft armament, for tanks and for landing parties of the Front line trenches.”
Sadly, we don’t get to see how the gun works but we can see the operator feeding the ball bearing projectiles into the hopper which has a powered feed system – he empties two cylindrical containers of balls into it one after another. It is unclear how many rounds might be in the containers, perhaps 50 each. The gun and its motor are mounted on a truck bed with a soldier in uniform, possibly aiming the weapon via a tiller.
Another of the later designs dating from the period came from Victor Czegka, a US Marine Corps Technical Sergeant, who is perhaps best known as the supply officer of Admiral Richard Byrd’s first two expeditions to the Antarctic. Czegka was granted a patent for a centrifugal machine gun in January 1922 (US #1,404,378).
Czegka’s 1922 patent (US Patent Office)
With some further digging I managed to find several articles referring to the gun in the US Army Ordnance Journal. Interestingly, a photo from the same demonstration is printed in one article, from late October 1920, with the caption confirming the man loading the weapon is the inventor, however, he isn’t named. The footage was filmed during the Second Annual Meeting of the US Army Ordnance Association. Another article dating from May 1921, also notes that the tests took place at Aberdeen Proving Ground, with the gun firing at 16,000 revolutions per minute which required 98 horsepower from the engine powering it. The gun apparently needed a “very rapid increase in power required for operation” when the speed of its revolutions was increased incrementally from 12,000 to 16,000 rpm. The article concluded that “a horsepower above 100 would have no material effect in increasing the speed” suggesting that a much more powerful, and therefore larger, engine would be needed to increase the revolution rate.
While researching I came across this set of images from a March 1922 edition of Popular Mechanics showing an unnamed centrifugal gun set up on a truck, powered by an engine on the truck bed. From the images it appears to be a gun similar to Moore’s with a single rotating ‘barrel’. The captions also note that the photographs were taken in New Jersey and Moore was a Major with the New Jersey National Guard, which may also indicate the gun is Moore’s.
Despite various designs seeing some US military testing none were ever adopted and relatively little information on them is available. It seems that they were relatively cumbersome weapons with extremely varying accuracy but this footage at least proves the concept. A short report in a may 1921 edition of Scientific American may shed some light, stating an unnamed gun was rejected “because of its great weight and its inability to obtain high initial velocity” concluding that “no centrifugal gun can have military value”. It appears that the range of the centrifugal guns was limited to the speed of their revolution, which in turn was limited by the power of the engine and motor that powered them. The larger the motor, the more cumbersome the weapon system was.
There are very few photos of centrifugal machine guns so stumbling across actual footage of one guns actually operating is very exciting. They are a fascinating tangent to the history of the machine gun – one that occasionally still garners interest.
A viewer shared a Pathe Newsreel with us which included more footage from the same demonstration. The footage title suggests it dates from 1938, however, I believe this to be incorrect.
Despite the incorrect date the footage shows us the internals of the centrifugal gun and its aiming mechanism!
The Type 64 is an integrally suppressed submachine gun designed in China in the early 1960s, taking several design elements from other Combloc small arms. The guns were manufactured at one of China’s State Factories (with the factory’s ‘66’ in a triangle marking in the left side of the receiver – this indicates the factory number, although available sources differ on which it refers to, either 66, 626 or 366).
Designed concurrently with the Type 64 suppressed pistol during the 1960s, the Type 64 SMG was developed for Communist China’s special forces for use in clandestine operations. Chambered in the standard 7.62×25 ComBloc pistol round, the Type 64 functioned best with Type 64 subsonic ammunition, a special subsonic spitzer projectile variation of the standard 7.62mm pistol round. It did not chamber the low power 7.65x17mm round used by the Type 64/67 pistols.
The Type 64 fed from 20 or 30 round double stack magazines which were reportedly developed from or at least influenced by the Soviet PPS-43’s double stack, double feed magazines. The weapon used a conventional blowback action and fired from an open bolt. Its maximum effective range was approximately 200 metres with two position flip up sights ranging out at 100 and 200 metres.
The Type 64 had a milled receiver with lightening cuts and weighed in at 7.6lb or 3.5kg unloaded. It took its bolt from the Russian PPS-43 submachine gun and a trigger group inspired by the ZB vz.26 light machine gun’s, which was well liked by the Chinese military.
The Type 64 shared a number of external similarities with the standard Type 56 AK-clone including its pistol grip, safety lever and under-folding stock (which is similar but slightly different to the Type 56-I’s under-folding stock).
The weapon has a number different controls including a conventional AK-style safety-come-dust cover, on the right side of the receiver – which blocks the travel of the bolt. On the opposite side of the receiver it has a two-position fire selector for semi and full-auto – you can just about reach these when the stock is folded. The forward position is for semi and the rearward position is full-auto. Finally, the 64 also has an additional trigger block safety, taken from the SKS, which pivots forward to prevent the trigger from being pulled.
According to a report written in October 1971, by the Small Arms Systems Lab of the US Army Weapons Command Research and Engineering Directorate, the weapon has an extremely high rate of fire of over 1,300 rpm.
A cyclic rate that high was the result of a combination of back pressure from the suppressor, the ammunition used and its blowback action. The Type 64’s chamber was fluted with three longitudinal cuts to aid extraction at its high rates of fire. It should be noted, however, that the 1971 US army tests were carried out with standard velocity ammunition – rather than the specialised subsonic Type 64.
The top cover is removed by pushing in what at first appears to be a spring-loaded detent, but is actually the recoil spring guide rod. The front of the top cover is held in the receiver by a lip which fits into a slot just above the breech. The top cover itself is a thin piece of stamped sheet metal with the serial number stamped at the rear.
With the top cover removed we can see inside the action. The 64 has a single recoil spring held in place by a guide rod. At the rear of the receiver is a small plastic buffer, designed to both soak up some of the recoil energy and to help reduce action cycling noise. There is an ejector on the left side of the receiver and guide rails along which the bolt moves. To remove the bolt it is pulled fully to the rear and then tilt it upwards.
The Type 64 is a pretty compact weapon despite the length of its suppressor. It has an under-folding stock, with two spring-loaded buttons at the rear of the receiver which have to be pushed in to fold and unfold the stock. When folded the weapon is 25in (or 63.5cm) long, with the stock adding 8 inches when it is deployed. The weapon can be used with the stock folded, although some of its controls are partially obscured.
The suppressor is contained by a housing which attaches to the receiver by an interrupted thread. The Type 64’s barrel was ported with 36, 3mm vents at the muzzle-end while the suppressor has 12 metal dished baffles held captive on a pair of guide rods. The weapon’s sights are mounted on the suppressor housing which attaches to the receiver by an interrupted thread. Sadly, I didn’t have time to strip the suppressor itself but the photos below, from my friend Chuck over at Gunlab, show the Type 64’s ported barrel and baffles well.
The 1971 Small Arms Systems Lab report found that the audible report of the gun, was 150db at the rear of the receiver and 157db 12 feet down range, however, this is probably not the best indication of the Type 64’s capabilities as the report states that the gun was tested with Chinese Type 51 standard velocity 7.62x25mm ammunition. Ideally, the weapon would have been used with subsonic Type 64 ammo specially developed for China’s suppressed pistol-calibre weapons. Chinese sources reportedly put the weapons noise level at 84db when using subsonic ammunition. The US report did note that while its noise suppression wasn’t outstanding, it very effectively hid its muzzle flash.
It appears to have been primarily used by Chinese scouts and special forces and saw action during the 1979 Sino-Vietnamese War. In the late 80s the Chinese replaced the Type 64 with the suppressed version of the Type 85 submachine gun, also chambered in 7.62x25mm, which used the same magazines, the Type 85 had a tube metal and stamped receiver which was simpler to manufacture than the 64’s machined receiver. The Type 85 has subsequently been superseded by guns like the bullpup Type 05.
Special thanks to the collection that holds this weapon for allowing me to take a look at it. As always guys thank you for watching. If you enjoyed the video please share it with friends and help us
The Galil rifle adopted by the Israeli Defence Force in 1972 was designed by Yisrael Galili and Ephraim Yaari of IMI following the disappointing performance of the FAL in service with the IDF since the early 1950’s. These failings of the FAL in service were mainly due to the poor reliability of the FAL with some of the mainly conscript troops in the field mainly down to poor maintenance and cleaning by the users in the field. The Israeli military found that captured AK47 rifles functioned more reliably without the routine maintenance that the FAL required, this was down to the finer tolerances and mechanism that the FAL employed whereas the AK47 could function reliably without the same level of cleaning and maintenance.
In the late 1960’s the IDF carried out a series of trials to select a replacement for the FAL. As part of those trials the following small arms were tested:
and a pre-production rifle from Beretta that ultimately led to the AR70 series rifle.
The result was that the AKM rifle came out as the winner of the trials but with some reservations. The Israelis didn’t like the stamped receiver of the AKM and as part of the trials they tested the Finnish M62 AKM variant rifle which had a machined receiver built from a steel billet which made it much more robust but heavy. This became the basis of what was to become the Galil.
A cold hammer forged barrel was selected together with a unitised front sight/gas block with a front sight base adjustable for elevation and drift adjustable for zeroing. The rear sight was positioned at the rear of the dust cover, which itself was strengthened to be more rigid than a standard AKM and allow the rear sight to maintain zero. The rear sight was an ‘L’ shaped flip type with positions for 300 & 500 meters. Flip up night sights were also fitted, they came with Tritium inserts. The folding stock was a virtual copy of the FN FAL Para type.
I won’t cover the Galil in any more detail as it has been covered by several others in great detail, what I will detail in future videos and articles is my own experiences of the semi-automatic ‘Sporter’ Galil rifles as well as the other IMI products that I have extensive knowledge of.
Meeting Yisreal Galili
Back in the early 1980’s IMI had been courted by several US companies to develop semiautomatic ‘clones’ of their military small arms. Action Arms worked with IMI and the UZI Carbine was developed primarily for US civilian sales by them from 1980. Following on from the UZI Carbine, semiautomatic versions of the Mini UZI and then the UZI Pistol were developed and sold.
Magnum Research Inc. as part of their partnership with IMI in developing the Desert Eagle pistol also marketed the semiautomatic versions of the Galil rifle in the USA.
In the UK at that time I was working part time as the armourer and technical advisor for the UK & Commonwealth distributor of IMI products Pat Walker Guns. I had worked with Pat since 1980 refurbishing and converting select fire and fully automatic ‘surplus’ small arms to semi-automatic only ‘civilian’ legal configuration for sale on the UK & Commonwealth collector/shooter market. This was a wonderful job as I got to travel a lot to see caches of surplus small arms and work on them… halcyon days!
In or around 1983, Pat acquired the IMI agency for the UK, and as part of that agreement we had to be trained on IMI products so we could service and support them as the distributor. In October 1984, we flew to Tel Aviv in Israel to attend the first (and possibly only) armourers course on the entire family of IMI small arms! The UK team consisted of myself, as the technical part of the team, Pat Walker as the UK agent/distributor, and Colin Greenwood who was the editor of the very popular UK shooting magazine GUNS REVIEW who was attending the course so as to write an article for said magazine.
Once we arrived in Israel we were accommodated in the Plaza Hotel on the beachfront in Tel Aviv. That evening we were introduced to the other attendees on the course who came from the USA, Germany, Italy, the Netherlands, Switzerland, Finland, and a South American country… We were introduced to some of the IMI personnel, which included Yisrael Galili, and given a rundown of the schedule for the next week.
During our time on the course we were given several ‘live fire’ demonstrations by none other than Yisrael Galili himself as well as Efrahiem Yaari (who would later go on to head up the special operations and weapons division of IMI as director in later years). We also got to handle and shoot all of the small arms IMI manufactured at that time including select fire versions and some prototype Desert Eagle pistols. In the evenings we were shown and also had to demonstrate how to strip, assemble, and troubleshoot all the IMI guns we had shot earlier that day… it became a source of entertainment that myself and the armourer of the Dutch distributor would see who could strip and reassemble each gun type the quickest… I won many a beer in those contests!
During one of the sessions where we were taught to strip the Galil, Yisrael Galili handed out some photocopies of a now infamous photo of the specially adapted Galil. He told us it was a special Galil for ‘mature’ IDF girls. Our friend Miles has a good article about the ‘Female Galil’ here.
We were given guided tours of the IMI manufacturing facilities seeing how each model and each family of small arms were machined and assembled. We also got to visit the IMI ammunition plant and saw manufacture there as well as test firing the civilian brand of SAMSON ammunition they manufactured.
It was with great pride that on the last evening we were in Israel we were each presented our armourers certificates and a commemorative book on the history of Israel by the Director of Sales Yehuda Amon at a presentation dinner in a restaurant in the ancient town of Caesarea. I also got to thank personally Mr Galili and Mr Yaarifor their excellent tuition and fantastic displays of weapons handling.
It was a fantastic opportunity for a then young man of 23 to get to work with such an influential smallarms company as IMI and get to meet such notable designers as Ysrael Galili and Ephraim Yaari. Sadly, the passage of time has robbed us of many of the people I shared that experience with Pat, Colin, and Mr Galili are sadly no longer with us. Luckily a few of those I met on the course are, and I still corresponded with them to this day.
Watch out for future articles and videos on my personal experiences with small arms.
Specifications for ARM (from 1983 factory brochure):
In 1981, Heckler & Koch introduced what would be their last infantry rifle that used their tried and tested roller-delayed blowback action, the HK G41. In October 1980, following NATO’s smalls arms and ammunition testing during the late 1970s, a meeting of NATO Armament Directors, agreed to standardise to the 5.56x45mm round favoured by the United States since the mid-1960s. Standardisation Agreement (STANAG) 4172 saw NATO standardise on the Belgian/FN SS109 ball round. At the same time Draft STANAG 4179 proposed adopting US 30-round M16 magazines as the standard 5.56 magazine pattern, while this proposal wasn’t ratified the M16’s magazine became the de facto standard.
At this time Heckler & Koch were engaged in a major engineering project to develop the G11 caseless ammunition-firing individual weapon. Their main offering for the 5.56x45mm rifle market at the time was the HK33, a rechambered version of the 7.62x51mm G3 developed by Tilo Moller, which was introduced in 1965. The HK33, however, used a proprietary HK magazine and was not compatible with the M16’s magazines. In 1977, as the NATO trials began and it became clear that 5.56x45mm would be adopted, HK began to develop what would become the G41. In 1979 with initial development completed HK submitted 18 G41s for testing with the West German Army. It wasn’t until 1981 that HK introduced the G41 onto the market.
While continuing to use the same roller delayed blowback operating system as the G3, HK33 and MP5, the G41 embodied a number of improvements. While still using a stamped metal receiver it utilised 1mm thick high tensile steel rather than the 1.2mm thick steel used by the HK33. This helped to lighten the receiver. The new rifle also used a lighter bolt assembly, paired with a new recoil spring which comprised of five wound strands around a central coil, rather than a single coil, which had a longer stroke. This acted to lower the felt recoil. The G41, however, had a higher rate of fire at around 850 rounds per minute compared to the 750 rounds per minute of the HK33. Some of the G41’s bolt geometries were reworked and a new extractor was added.
The G41’s lower receiver was redesigned to allow the rifle to feed from STANAG magazines rather than HK’s earlier proprietary magazines. The cocking lever and forward assist were taken from the HK21A1 (XM262) general purpose machine gun, developed for the US SAW trials.
It also had a new more triangular polymer foregrip and added a plastic dust cover to the ejection port, a NATO pattern optics mount (meeting STANAG 2324) replaced HK’s claw-mount system, and a spring-loaded folding carrying handle near the centre of balance was added. Importantly it also added a last round hold open device and a bolt release catch, on the left side of the lower receiver.
The usual thumb serrations on the side of the bolt, for pushing the bolt home, were replaced by a prominent forward assist, similar to that found on the M16A1 and other HK weapons such as the HK21 light machine gun and the PSG-1 sniper rifle. HK sales literature described it as a ‘low noise’ forward assist and the manual describes the “quiet cocking of the weapon” – essentially riding the cocking handle back into battery and then pushing the forward assist to lock the action, the system is not as ‘low noise’ as advertised.
Another important feature of the rifle was the inclusion of a three-round burst setting alongside semi and fully automatic. The G41 could mount a standard G3 bayonet, fit an M16 bipod and had a flash hider designed to enable it to fire NATO standard rifle grenades. The 40mm HK79 under barrel grenade launcher could also be mounted to all variants of the G41, simply swapping it out for the polymer forend. HK referred to this set up as the G41-TGS or ‘Tactical Group Support system’.
The G41 came in a number of variants with designations A1 to A3. The base rifle had a fixed buttstock and its rifling had 1 turn in 7 inches with a right-hand twist, in a 18.9 inch barrel. The A1 had a 1 in 12” twist barrel and fixed buttstock. The A2 had a collapsing, single position stock and 1 in 7” inch twist rifling, while the A3 had 1 in 12” inch twist rifling. The 1 in 7” rifling was optimised for the new SS109, while the 1 in 12” optimised for the US M193 round. There was also a shortened G41K model which had a collapsing stock and a 15 inch barrel available with both rifling types.
One of the main issues with the G41 was its weight. Despite efforts to lighten the sheet metal receiver, it weighed more than its predecessor the HK33. According to measurement data compiled by researcher Nathaniel F, unloaded the G41 weighs in at 4.31kgs or 9.5 lbs, this is a full pound heavier than the HK33. A contemporary M16A2 weighed 3.39kg or 7.5 lbs while the Spanish CETME L, a similar stamped receiver rifle chambered in 5.56×45, weighed 3.72kg or 8.2 lbs. The rifle eventually adopted by the Bundeswehr, the HK G36, weighed 3.13kg or 7.3 lbs. The G41K with its collapsing steel stock wasn’t much lighter, weighing 4.3kg or 9.5 lbs, according to HK sales literature. Another potential issue may have been reliability with the move to the STANAG magazine rather than the optimised proprietary HK magazines may have introduced some issues.
Following NATO’s decision the early 1980s saw a large number of countries looking to replace their ageing 7.62x51mm battle rifles. Sweden began to look for a 5.56x45mm rifle to replace its licensed version of the G3, the Ak4, in the late 1970s. HK could initially only offer the HK33 but the G41, tested later, was also rejected by the Swedes in favour of FN’s FNC. Italy sought to replace the BM59 with a more modern rifle and HK entered into an agreement with Luigi Franchi which saw them offer both the original HK configuration and the develop their own, slightly modified version, the Franchi mod. 641, but the Beretta AR70/90 was selected. Similarly, in 1984 Spain decided to adopt the indigenously developed CETME L. In 1986 the HK G41 was also submitted to the Irish Army’s trials to replace the FN FAL, it was beaten by the Steyr AUG. Initially West Germany had hoped to procure up to 20,000 HK G11 rifles per year, with a total of 224,000 in service by 2003.
The collapse of the Soviet Union and the subsequent reunification of Germany saw Federal budgets stretched and the G11 programme was subsequently abandoned entirely. The Bundeswehr still needed a suitable rifle to replace the G3 and in the 1990s sought a lighter weight rifle. HK felt their HK50 project, in development since the mid-1970s was a better bet than the heavier G41, and following Bundeswehr trials the G36 was subsequently adopted in 1997. Sadly, I have not been able to get a hold of any of the trials reports from the nations that tested the G41, so can not say with certainty why the countries mentioned above rejected HK’s rifle.
From photographs of members of the Turkish Gendarmerie special operations group training at the Foça Commando School, dating from the early 2010s, it appears that Turkey either purchased a number of G41s or Turkey’s state-owned defence manufacturer, MKEK, produced an unknown number under license.At some point in the 1980s the British Army also tested a small number G41s with serial numbers #11131, #11832 and #11833 remaining in UK collections.
Denmark’s elite Jaegerkorpset and Froemandskorpset used the G41 for a time and Argentina’s special forces, including the Grupo de Operaciones Especiales, have also been photographed with both HK G41s and G41A2(collapsing stock) fitted with the TGS package comprising of the HK79 under barrel grenade launcher.
The G41 represents the last evolution of HK’s infantry rifles using the roller delayed blowback action. It comes from a period when HK were developing what they hoped would be the next generation of small arms technology and with the collapse of the G11 programme and the lack of interest in the G41 the company faced financial uncertainty throughout the early 1990s. HK’s move away from the roller delayed blowback action to a more conventional gas operated rotating bolt system, combined with lightweight polymers, in the G36 proved to be more successful than the ill-fated G41.
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Our thanks to the collection that holds the G11 for the privileged and nerve-wracking opportunity to field strip it and take a look inside. If you’d like to know more about the history of the G11’s development you can check out our video and full blog on it here. Vic has done a great series of videos looking at the G11 and the other prototype rifles from the US Army’s abortive Advanced Combat Rifle trials – you can find those here.
In this blog we’ll take a closer look at some of the G11’s components, for a demonstration of dissassembly and and explanation of how the rifle works in principal check out the video above.
Firstly, lets take a look at the exterior of the rifle. The weapon has a box-like polymer coated outer shell. The shell is made up of three parts, with the butt assembly and forend locking into the centre assembly which includes the pistol grip, trigger mechanism and optical sight. The forend and butt are locked into the centre assembly by plastic locking tabs. While stiff and somewhat difficult to depress the tabs are reportedly prone to breaking.
Before we look at the G11’s internals lets take a look at the shell components. Here we can see the inside of the forend, we can see a metal (aluminium I believe) barrel tube into which the barrel slides.
Below is a photograph of the rear of the centre assembly looking forward, the small white circle (sadly slightly out of focus) is the bushing the barrel protrudes through into the forend.
Next we have a view of the inside of the rifle’s butt assembly. Note the scuff marks on the inside where the centre assembly has scrapped the plastic. We can also see the locking tab windows which are on the top and bottom of the butt.
Inside the butt we can see the ‘toothed wheel’ and ‘sealing gear’ which are turned when the cocking piece is rotated. These plastic pieces act directly on the action. Behind that is the gas escape valve, which will tap off excess gas if over pressure problems occur with the rifle.
The first step to disassembling the G11 is ensuring the weapon is clear by pushing the cleaning brush up into the breech.
Lets now take a look at the rifle’s action up close, below we can see the G11 with its forend and butt assembly removed. Next to it is the breech cylinder and control disk.
Here are some photos of the action from various angles:
Here’s some close ups of the breech cylinder and control disk:
Here are some close ups of the various parts of the action:
According to the 1989 armourer’s manual, provided for the ACR trials, the G11 is made up of a total of nearly 450 individual parts. 144 of those make up the G11’s breech assembly.
With the breech and barrel assembly removed from the centre assembly here’s a diagram I put together showing most of the component parts of the G11’s action:
Next lets take a look at the G11’s barrel assembly with its recoil management system and gas piston:
Finally, here’s a photo of the G11 broken down into its major component assemblies: magazine, forend, centre assembly breech & barrel assembly and butt stock:
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HK G11- ACR. Armourer’s Manual for Maintenance of Repair of Rifle, 4.92mm, ACR, March 1989 (source)
Today we’re examining an intriguing firearm with a fascinating history. It is difficult to understate the potential importance of the Curtis Rifle. Despite being designed in Britain in the 1860s the firearm gained more notoriety when it was offered as evidence in a legal battle between the Winchester Repeating Arms company and Francis Bannerman. What makes the firearm most noteworthy, however, is its fundamentally unconventional layout. Designed by William Joseph Curtis in the mid-1860s, it is arguably one of the earliest ‘bullpups’ and almost certainly the first repeating bullpup.
For the purpose of this article it would be wise to first define what a bullpup actually is. It can be defined as a weapon with a somewhat unconventional layout which places the action and magazine behind the weapon’s trigger group. This has the benefit of maintaining a conventional rifle’s barrel length while making the overall length of the rifle more compact.
Bullpup rifles became popular with a number of militaries around the world during the 1970s and 1980s – namely the Austrian Steyr AUG, the French FAMAS and the British SA80, and more recently with rifles from China and Singapore as well as the Tavor series of rifles from Israel.
The bullpup, however, dates back much further with some argument to be made for the first firearms to utilise the concept being 19th century percussion target shooting rifles. The earliest military bullpups date to the beginning of the 20thth century, these include a rifles designed by Samuel McClean, the initial designer of the Lewis Gun, patented in 1896 (US #723706), by Major Philip Godsal (US #808282) and a carbine developed by James Baird Thorneycroft in 1901. Thorneycroft subsequently worked with Moubray Gore Farquhar and Arthur Henry Hill to patent a refined version of the carbine in 1905 (US #827893). While the Thorneycroft was tested by the British army it was rejected due to ergonomic and reliability shortcomings.
William Curtis’ design, however, predates all of these. Patented in Britain on 10th July, 1866, Curtis is listed by the London Gazette as a Civil Engineer. His design is unlike anything that had been seen before. Based on a slide-action with a drum magazine, it was placed over the shoulder – much like a modern shoulder-fired anti-tank weapon.
Curtis’ rifle is probably the very first bullpup magazine rifle, one of the earliest to have a drum magazine (an Italian, Marco Antonio Francois Mennons, patented an earlier design for a drum magazine in March 1862, GB #637) and also an early striker-fired design. Clearly a design well ahead of its time and radically unconventional.
This unconventional gun’s designer was born in Islington, London in 1802, as a civil engineer he worked on Britain’s rapidly growing railway network. He died in 1875, placing the development of his rifle nearer the end of his life. With hindsight Curtis’ design clearly had revolutionary potential but it appears that his concept was never taken up. It appears that he only patented his design in the United Kingdom. If not for a corporate lawsuit on another continent, decades later, then it is possible Curtis’ design, like so many others, would have slipped into historical obscurity.
Francis Bannerman vs. the Winchester Repeating Arms Company
In 1890, Francis Bannerman VI, a successful entrepreneur specialising in junk, scrap and later surplus, purchased the Spencer Arms Company and the rights to their patents. The company had been founded by Christopher Miner Spencer, designer of the Spencer Rifle, they produced the first commercially successful slide or pump-action shotgun. This pump action shotgun was designed by Spencer and Sylvester H. Roper and patented in April, 1882 (US #255894). Bannerman continued producing the shotgun as the Bannerman Model 1890, however, in 1893 the Winchester Repeating Arms Company, introduced the John Browning-designed Model 1893 pump shotgun (US #441,390).
In response in October 1894, Bannerman filed a law suit against the Winchester Repeating Arms Company claiming that the slide/pump actions used by Winchester’s Model 1890 and new Model 1893 shotgun infringed on the patents that he owned.
He called for the court to force Winchester to halt production and claimed $10,000 in damages and royalties for the sale of guns which he believed infringed his patent. Winchester temporarily halted production of the Model 1893, in the meantime Bannerman continued producing and improving his shotgun introducing the 1894 and 1896 models.
Various contemporary newspaper reports suggest between 100,000 and 500,000 people were directly interested in the case as ordinary owners were liable under the conditions of Bannerman’s suit.
Winchester dispatched George D. Seymour to Europe to scour the French and British patent archives for any patents for similar actions that had been filed there before those now owned by Bannerman. Winchester discovered four patents: three British and one French. The earliest of these was Alexander Bain’s patent of 1854. Two more patents held by Joseph Curtis and William Krutzsch were found, dating from 1866. The later French patent was filed by M.M. Magot in 1880. All of these designs, including the Curtis we are examining here, never progressed beyond the development stage and were largely forgotten until rediscovered by Winchester.
Winchester claimed that these earlier designs invalidated Bannerman’s patent claims. To illustrate their defence Winchester decided to build working models of each of the designs, breathing life into long forgotten patent drawings. This must have been a major engineering task as the patent designs would not have had all the information needed to produce a working model.
In 1895-96 Winchester engineers, including T.C. Johnson, assembled working models of each of the designs to prove their viability. These were tested and Winchester’s lawyers took them into court and submitted them as evidence, even offering a firing demonstration. The court declined the demonstration and made its decision on June 27th 1897. Judge Hoyt H. Wheeler of the United States District Court for the Southern District of New York ruled in favour of Winchester and threw out Bannerman’s suit.
Winchester had produced some 34,000 Model 1893s before, in November 1897, they introduced the improved Model 1897 which proved to be hugely popular on both the civilian and military markets. Bannerman unveiled a final shotgun, the Model 1900, but production ended in the early 1900s.
Curtis’ Unconventional Design
Curtis’ design encapsulates a number of features which, in 1866, were unheard of and arguably revolutionary. Not only is it probably the first magazine-fed repeating bullpup but it also uses a drum magazine, something that would not see substantial military use until the First World War. It has a folding shoulder support or stock, uses a striker fired action and makes use of self-contained ammunition.
The Curtis’ rifle is placed over the top of the user’s shoulder with a folding leather strap which fits into the shoulder pocket. Curtis’ original patent also suggests a fixed hook and strap. The user then grasps the loop near the muzzle with their support hand and the trigger and bolt handle with their other hand. Novel, but not the most ergonomic of designs.
The magazine appears to hold at least 13 or more rounds according to the available patent and Winchester’s engineering drawings. The magazine is fixed in place and rounds appear to have been fed into it through the loading/ejection port on the left side of the weapon. This would have also put spent cases being ejected right next to the user’s neck. Curtis’ patent explains that the magazine has a spring inside which has a length of string attached to the top of it which the user can pull back to depress it and allow cartridges to be loaded into the drum. The magazine has a single stack or loop of cartridges. Once loaded the string can be released, allowing the magazine spring to push rounds into the action.
The Curtis rifle’s action appears to lock at the front of the weapon with the bolt handle acting on a hinged, spring-loaded, locking piece or flapper which dropped into place when locked. To unlock the action the bolt handle was sharply pulled to the rear which pushed the locking piece out of engagement and unlocked the action allowing the operating rod to be cycled.
The weapon’s chamber appears to be just forward of the centre of the drum magazine with the striker assembly located behind it. To operate Curtis’ rifle the magazine was loaded and then the user had to unlock the action by pulling the bolt handle backwards. This then allowed the operating rod to be pulled backwards, like a pump action, which pushed the bolt and striker assembly to the rear, cocking the striker, the bolt handle was then returned forward and locked back into position. This chambered a round ready to be fired.
The trigger at the front of the firearm is connected to the striker assembly by a long length of wire. When pulled the wire becomes taught and trips a sear to release the striker, firing the weapon.
Originally Curtis’ patent describes how ‘small punches’ on the bolt face would pierce the cartridge base during firing to enable the spent case to be extracted once the action was cycled. From Winchester’s engineering drawings, however, it appears they replaced this with a more reliable and conventional extractor at the 7 o’clock position of the bolt face.
Given that the weapon would have fired black powder cartridges it is unclear how well the rifle would have faired with sustained firing. The drum magazine would have been susceptible to jamming as a result of powder fouling. This, however, would not have been an issue for Winchester later version of the rifle.
But the Curtis has one more interesting surprise. The original 1866 patent also includes what might be one of the earliest descriptions of a gas operated firearm. One of the most fascinating sections of Curtis’ original patent details how the rifle might have been adapted for gas operation:
“An arrangement is shown in Fig.10, in which the rod G is dispensed with; in this case the barrel may be shorter, not projecting beyond the shoulder; the butt is similar. The breech may be opened automatically by the powder gases, which pass by an opening in the barrel to a cylinder with which works a breech operating plunger.”
Curtis does not go into further detail but he is clearly describing a piston-driven, gas operated system. The patent drawing also depicts an alternative tube magazine instead of the drum magazine.
It is unknown if Curtis ever put his theory to the test and developed his gas system idea further. It is tempting to wonder if, in 1895 when Winchester were assembling their model of the Curtis, if John Browning or William Mason, who were also developing their own gas operated systems at the time, were aware of Curtis’ idea from 30 years earlier. As such Curtis’, admittedly vague, gas system pre-dates the first patents on gas operation by just under 20 years.
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Action: Slide action
Calibre: .32 Winchester Centre Fire
Feed: ~12 round drum magazine
My thanks to the Cody Firearms Museum at the Buffalo Bill Center of the West for allowing me to examine and film the Curtis. Special thanks to the CFM’s assistant curator Danny Michael for making extra time to open up the case where the rifle Curtis is on display so we could examine it and for also sharing Winchester’s technical drawings and other records.
Thanks also to David Minshall of Research Press.co.uk for his assistance finding Curtis’ original British patent abridgement and to John Walter for digging up some additional information about Curtis’ life.
‘Winchester Suit Decided’, The Times (Philadelphia), 27th June, 1897
‘Recollections of the Forming of the Pugsley & Winchester Gun Collections: A Talk Given by Mr. Edwin Pugsley at the New Haven Meeting of the AS of AC’, September, 1955.
By the Autumn of 1940, Nazi Germany controlled most of mainland Europe, France had surrendered, and the British Army had been forced to evacuate the continent and in the process had lost much of its arms and equipment.
Arms production in Britain was ramped up in order to arm the returning troops and the new units being formed to defend against the imminently expected German invasion. Existing designs like the Bren light machine gun and the Lee-Enfield Rifle were simplified to increase production however new options were also examined. The cheap, quickly manufactured STEN submachine gun was introduced and calls were made for a simplified light machine gun which could be made in any machine or workshop with simple tooling. Even before the fall of France the British Ordnance Board sent out a memo in June 1940, requesting a light machine gun which could be produced in garages and smaller workshops throughout Britain in the event that the Royal Small Arms Factory at Enfield was bombed.
In December 1940, the Chief Superintendent of Design outlined a light machine gun based on the Lewis Gun’s rotating bolt, which fed from Bren gun magazines.
The Birmingham Small Arms company (BSA) were approached to develop a design. BSA tasked their chief designer, Henry Faulkner, with the project. Members of the British Army’s Ordnance Board, however, began to question the decision to have an established manufacturer build a prototype for a gun that was supposed to be assembled in small ad-hoc workshops. As a result the contract was cancelled, however, BSA and Faulkner persisted anyway.
Faulkner, with the help of Roger Wackrow, came up with a weapon which later became known as the BESAL. The design was developed to be simple, cheap and quick to manufacture. The standards of finish were significantly lower than those of the standard Bren then in production. The plan was to issue the BESAL in the event Britain’s armed forces found themselves engaged in a last ditch defence with German invasion either imminent or already underway.
Faulkner’s design was chambered in .303 and fed feeding from standard Bren gun curved box magazines. It used a basic trigger mechanism, a simple pressed gas cylinder and a body held together by pinning and spot welding. The first prototype had a folding but non-adjustable bipod and a skeleton butt stock with a wooden insert. With the manufacture of barrels expected to be a bottleneck to the weapon’s production it was suggested that the spare barrel issued with each Bren gun be recalled for use in the new BESAL. This clearly illustrates just how desperate the situation was expected to be. The first prototype BESAL was ready by late 1941, and testing began in March 1942. The BESAL proved to be reliable and effective during trials.
Faulkner’s design went through a number of iterations but the gneral design had been finalised by May 1942 when BSA, Faulkner and Wackrow filed three patents protecting the design. The principle feature of the later BESAL patterns was the use of a cocking system which saw the operator push the pistol grip forward to catch the bolt, and then pull it to the rear to cock the weapon. This is a system that was later seen in the Czechoslovakian Vz 52/57, 59 series and the Finnish KVKK-62 general purpose machine gun.
Iterations of the BESAL:
(Artists impression of 1st BESAL prototype – from Dugelby’s Bren Gun Saga)
Right side cocking handle
Simple fixed peep sight
Non-adjustable bipod mounted on the receiver
(Photograph of a 2nd Pattern BESAL with a pan magazine, note the right-side cocking handle – from Dugelby’s Bren Gun Saga)
Bipod moved to front of the gas tube
Universal magazine adaptor fitted for Bren and Motley Pan magazines
Full wooden stock – similar in profile to the Lewis Gun’s
Disassembly knob introduced
Pistol grip cocking mechanism replacing the conventional cocking handle
(Photograph of a 4th Pattern BESAL, note the selector on the pistol grip – from Dugelby’s Bren Gun Saga)
Introduction of a selector switch on the left side of the weapon’s pistol grip
In August 1942, BSA submitted the 3rd Pattern Prototype for trials. It was extensively tested between September and November 1942. On 6th January, 1943, BSA renamed the BESAL the ‘Light Machine Gun, Faulkner, 0.303-In Mk1’ in order to prevent confusion with the 7.92x57mm BESA machine gun used in some British tanks. The BESA, also produced by BSA, used a similar pistol grip cocking mechanism. We hypothesise that the the BESAL’s name might come from the BESA, meaning BESA-Light. This, however, is unconfirmed.
It seems that over time as BSA and Faulkner improved and refined the design the BESAL ceased to be a cheap, simple, quickly-made alternative to the Bren. Instead it appears that BSA hoped the weapon might be adopted as a somewhat cheaper substitute standard to the Bren. Final testing of the BESAL were held in March 1943, but by now the weapon’s original purpose had been made defunct by the huge increase in Bren manufacturing capacity. By 1943 the Bren was in production on four continents: at Enfield in the UK, at John Inglis in Canada, at Ishapore in India and Lithgow in Australia. Inglis alone was producing 10,000 Brens a month by 1943.
With the need for a new light machine gun gone the BESAL project was cancelled in June 1943. BSA produced an estimated 20 guns, of various patterns, during the BESAL development project. Today, it is believed that only a handful remain.
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Length: 118.5cm (46.6in)
Weight: 9.7kg (21lb 8oz)
Barrel Length: 56cm (22in)
Action: Gas operated, short recoil
Feed: 30-round Bren box magazine or 100-round Motley pan magazine
Cyclic Rate: 600rpm
The Bren Gun Saga, T. B. Dugelby (1999)
Bren Gun, N. Grant, (2013) Military Small Arms, I. Hogg & J. Weeks (1985)
Modern Small Arms, F. Myatt (1979)
‘Improvements in or relating to gas-operated automatic firearms’, GB572925, BSA, H. A. Faulkner & R.D. Wackrow, 30/10/1945, (source)
‘Improvements in or relating to automatic firearms’, GB572926, BSA, H. A. Faulkner & R.D. Wackrow, 30/10/1945, (source)
‘Improvements in or relating to automatic firearms’, GB572924, BSA, H. A. Faulkner & R.D. Wackrow, 30/10/1945, (source)