Heckler & Koch MP5K Briefcase Gun

Officially designated by Heckler & Koch as the ‘Spezialkoffer’ or Special Case, the Briefcase Gun, sometimes referred to as the Operational Briefcase, is a clandestine weapon system designed for personal protection details. The ‘Special Case’ was introduced in the late 1970s offering the firepower of an MP5K in a concealed package which could be rapidly brought into action.

A view of the case’s exterior (Matthew Moss)

While the MP5K is already a compact weapon that can be carried concealed under a coat or tucked under the arm, the Special Case, in theory, allowed the weapon to be carried in an instantly accessible way. One H&K leaflet stated that the case retains “approximately the same rapid readiness to fire” as an unconcealed submachine gun. The case had the added advantage of being able to be operated with just one hand.

A view of the case open with MP5K mounted (Matthew Moss)

To build the brief case Heckler & Koch turned to Hofbauer GbmH, a German manufacturer that specialises in extrusion blow moulded protective cases for tools and equipment, to make the case body. The case is made from black plastic moulded over an aluminium body with a stainless steel locking clasps and a strip of silver trim tape around the lower half. Inside on the right hand rim of the lower half of the case is the case maker’s marking ‘Hofbauer Boss Flanegg’.

DSC_0684 - Copy — Close up of the case’s Hofbauer markings (Matthew Moss)

Inside the case Heckler & Koch used a modified STANAG claw mount, with a modified release lever, that was normally used to mount optics on G3s and MP5s. The claw mount system holds the weapon in place and a firing mechanism connects a trigger in the briefcase’s handle to the weapon’s trigger inside. The weapon itself is an MP5K, the example we’re examining today has a ‘SEF’ selector and the contoured stahl G3 griffstück (pistol grip assembly). The MP5K was first introduced in 1976, reportedly developed following a request from the security detail of a South American head of state.

The muzzle of the MP5K’s 4.5 inch barrel fits into a tube or shroud in the left side of the case. Below the weapon is a clip to hold a standard plastic MP5 cleaning kit. While inside the lid of the case there is a clip to hold a spare magazine. The MP5K-PDW, introduced in the early 1990s, will not fit into the case as the muzzle and folding stock prevents it from fitting.

A close up of the cases muzzle ‘tube’ and rubber muzzle cap (Matthew Moss)

The trigger in the case’s handle works through a series of linkages which connect it with the MP5K’s trigger. Pulling the external trigger upwards pulls an linkage forward which in turn acts on a pivoted arm which pulls the weapon’s trigger. The case has a built in safety on the left side of its handle. When pulled to the rear with the thumb it moves a blocking bar backwards and allows the trigger, inside the handle, to travel upwards to fire the weapon. There is some variation to the trigger mechanisms with a slightly dog-legged, rather than straight, trigger arm being introduced to allow the use of MP5Ks with ambidextrous selectors.

HK briefcase trigger — The cases’s handle disassembled, showing the trigger mechanism (courtesy of Nicholas Chen)

Once fired the spent cases are deflected down into the body of the case and can only be removed once the case is opened to reload or remove the weapon from the case. There is no ejection system built into the case.

In addition to the case we have examined in this video/article, there is also another version based on a leather satchel-style briefcase, known as the ‘Spezialtasche’ or Special Bag. Instead of the moulded plastic case the MP5K is held inside a leather case with a ‘reach-inside opening’, which allows the user to put their hand inside the case and hold the pistol grip and operate the weapon’s controls. The gun is still held in the same kind of cradle claw mount but the leather case does not have the integrated trigger in its handle. The upper half of the case, held in place by four snap buttons, could come free of the lower section to allow the MP5k to quickly be accessed for reloading and removal from the claw mount.

HK Briefcase and Satchel — Late 1970s H&K product sheet for ‘Spezialkoffer’ or Special Case & leather ‘Spezialtasche’ or Special Bag (source)

As you would expect aiming a briefcase is no easy feat, the Special Case was intended for engaging targets at very close ranges or gaining initial fire superiority, suppressing a target long enough to either deploy the MP5K properly from the case or extricate the principal being protected. One of the major issues with the case is naturally limited access to the weapon which makes changing fire more, clearing stoppages and reloading impossible without opening the case – which can only be accomplished by opening the case’s two locking clasps, which in a contact situation would take precious seconds of fumbling.

Here’s what appears to be some vintage promotional footage showing the case in action:

A substantial number were sold, especially to Middle Eastern countries. During the 2003 Invasion of Iraq, the troops from the US 7th Infantry discovered a cache of 24 H&K Briefcases untouched, like new in their wrappings, bought by Saddam’s regime. Heckler & Koch continue to offer the case, two models are currently listed on their website: the original briefcase, now referred to as ‘Schießkoffer’ or ‘shooting case’, and a quick deploy ‘Zerfallkoffer’ case (offered for both the MP5K and the MP7) .

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Specifications (taken from H&K data sheet c.1984):

Case:

Case External Dimensions: 17.24×4.25×12.67in (438x108x322mm)
Weight of case without MP5K: 3.3 lbs (1.5kg)
Weight of case with unloaded MP5K: 7.72lbs (3.5kg)
Weight of case with MP5K + 60 rounds: 14.88 lbs (6.75kg)

Weapon – MP5K:

Length: 12.8in (32.5cm)
Weight (unloaded): 4.4 lbs (2kg)
Barrel Length: 4.5in (11.4cm)
Action: Roller-delayed blowback
Calibre: 9x19mm
Feed: 15 or 30-round magazines
Cyclic Rate: 900 rpm

Bibliography:

Full Circle: A Treatise on Roller Locking, R. Blake Stevens (2006)

The Gray Room, J. Phillips (2010)

‘HK Operational Briefcase: German design, MP5 included’, Guns.com, C. Eger, (source)

‘H&K MP5K Briefcase: Luggage you can fire’, TFB, R. S., (source)

‘Review: H&K MP5K Briefcase And My Modifications’, TFB, N. Chen, (source)

H&K MP5 brochure c.1985, via Small Arms Review Reference Library (source)

H&K Special Case datasheet c.1979, via Small Arms Review Reference Library (source)

H&K German factory datasheet c. late 1970s for cases, via Small Arms Review Reference Library (source)

Special thanks to the collection that allowed us to examine and film the HK Special Case.

Winchester Experimental Submachine Gun

Held in the collection of the Cody Firearms Museum (CFM), at the Buffalo Bill Centre of the West, is a most intriguing Cold War submachine gun. The weapon came from the collection of the old Winchester Firearms Museum, which the CFM inherited, it is not a test & evaluation weapon made by another company but a submachine gun designed and developed by Winchester. Those who know their Winchester history will know the company had no prior background in submachine gun design, instead being best known for their rifles and shotguns.

left N4 and N2 — Left side profile view of the N4 and N2 Winchester submachine gun prototypes with their stocks folded (Matthew Moss)

Very little is known about Winchester’s submachine gun project, but two prototype examples survive, an early ‘in the white’ model labelled ‘N2’ and another which Herbert Houze, the CFM’s former curator, designated ‘N4’ . The documentary evidence for the Winchester submachine guns is sparse, amounting to just entries in the Winchester Museum’s inventory and a faded battered item tag attached to N2. A confusing element is that the inventory simply refers to the two prototypes as N-1 and N-2, with no mention of an N4.
There is also believed to be original engineering drawings housed in the Winchester Archival collection, currently held by the McCracken Research Library, but searches by myself and library staff have been unable to locate these.

It is unclear if the tag from N2 is contemporary, perhaps added when the gun was handed over to Winchester’s museum, or if it was added later. In under 100 words it give us a short potted history of the N2 itself and the company’s programme to develop a submachine gun.

N2's item tag — Close up of the N2’s item tag detailing the gun & program’s history (Matthew Moss)

Houze suggests the development programme began in 1955 and the tag attached the N2 suggests that development ceased in 1957, whether this is solely for that gun or the entire programme is unclear. This would make Winchester’s weapon a contemporary of the famous Israeli UZI.

The tag describes the N2 as a 9mm blowback ‘NATO Burp Gun’, followed by the name A.A. Arnold, a Winchester engineer perhaps best known for writing a series of manuals for Winchester firearms, followed by ‘dropped Dec ’57’. In his 1994 book, Winchester Repeating Arms Company: Its History & Development from 1865 to 1981, Houze suggests that the weapons were designed by A.A. Arnold and Melvin M. Johnson in 1955, for possible adoption by NATO. The association with NATO might also be the origins of the ‘N’ prefix. I have been unable to find any published patents attributed to Arnold, Johnson or the company relating to the experimental submachine gun.

I contacted NATO’s Archives who advised that they were unable to find any reference or documentation relating to a direct NATO submachine gun requirement. Another possibility is that the weapon was developed to market more broadly to NATO member nations. The submachine gun market at this time in Europe, however, was already saturated by both wartime surplus and a new generation of guns, including the Sterling, the UZI, the Madsen M50, and the Carl Gustav m/45.

N2 prototype — Right side profile view of the N2 ‘in-the-white’ prototype with its stock deployed (Matthew Moss)

The reverse of the N2’s label documents the prototype weapon’s reliability and feeding problems. The tag states that the N2 did “not eject well” and that the bolt slide assembly was too heavy. It also highlights failures to cycle properly with extracted cartridge cases catching under the firing pin. The label then gives a brief description of some of the N2’s features: “fixed firing pin, 33x Mag. Folding stock.” Interestingly, it also notes that the weapon would be cocked by a rod – the hole for which had not yet been added. The tag ends with a suggestion that the heavy one piece bolt assembly should be lightened.

N2 Tape — Close up of the N2’s difficult to decipher tape note (Matthew Moss)

N2 itself also has a piece of masking tape, on the recoil spring assembly cover, with its serial number and calibre written on it, along with A.A. Arnold’s name and some words that are too difficult to make out, but include ‘feed’.

Houze has also suggested that Melvin Johnson, designer of the Johnson rifle and light machine gun who joined Winchester as a designer and adviser in the early 1950s for a short time, and Stefan Janson, designer of the Brtish E.M.2 bullpup and subsequent Winchester engineer, both worked on the project. However, I have been unable to find any documentary evidence of their involvement.

Examining the N2:

N4 and stripped N2 — Winchester N4 and disassembled N2 prototype (Matthew Moss)

We can learn a lot from hands on examination of the two Winchester ‘N’ prototypes. Examining N2 we find that the receiver is made up of a piece of shaped sheet metal with a rounded upper half containing the barrel, bolt and cutouts for the grip points on the bolt assembly that allow charging. The bolt assembly rides over the rear portion of the barrel and projects back into the receiver. The lower section of the stamped receiver is rectangular and has a cut out for a separate magazine housing and fire control mechanism consisting of a trigger and push through safety – which we did not remove during disassembly. The N4 is missing its safety.

In the N2, the magazine housing is held in place by the stamped metal trigger guard which rocks into a notch behind the trigger and at the front interfaces with a notch in the magazine housing which has to be placed in the receiver at the same time, both are then held in place by a screw. This was changed in the later ‘N4’ with the trigger guard as a separate independent piece.

Winchester N2 Prototype Reassembly:

The side plates, muzzle end cap and recoil spring assembly cover all made from Aluminium – ostensibly to reduce weight. The submachine gun prototypes both use a pinch cocking method similar to that seen in the earlier British BSA WELGUN developed during WWII. The recoil spring proved to be too strong to cock easily, the addition of ‘rod’ cocking handle is suggested on the N2’s tag. The blued, later N4 prototype, however, is still lacking a conventional cocking handle. The pinch cocking method is not ergonomic, the user’s fingers could easily be caught by reciprocating bolt in charging cut outs in the receiver.

The N2 prototype disassembled, sadly we were unable to free the bolt from the receiver (Matthew Moss)

Another ergonomic consideration is the Winchester’s submachine gun’s unusually swept back pistol grip angle, the angle of the forward grip made by stock when folded is also similarly angled. Both the weapons have a push though safety selector just above the trigger (likely safe & fully automatic, but could not check as gun unable/difficult to cycle the prototypes easily). The weapon likely fed from a double stack, single feed magazine – either of an similar pattern to the MP40 or proprietary. The N4 seen in Houze’s 1994 book is shown with an MP40 magazine. UZI magazines fit the weapon but don’t lock into place.

The basic design does not change substantially between the prototypes with the control configuration, folding wire stock, pistol grip angle and magazine housing dimensions remaining the same. The N4, however, differs from the earlier prototype in a number of respects. The N4’s nose cap now fits over the rounded half of the receiver, rather than sitting flush and the cut outs in the upper receiver to access the bolt assembly for charging have been moved back slightly.

N4 close up — Right side view of the N4 blued prototype, note the half cocked bolt and the narrower grip serrations on the bolt assembly. Note also the intersection points of the recoil spring assembly cover and the upper receiver (Matthew Moss)

The later N4 model has pins in place of some of the screws used on the N2. The side plates have been replaced by a one-piece recoil spring assembly cover which projects back further over the magazine housing to the rear of the receiver. The most fundamental difference between the two is that it appears that the front part of the N4’s receiver has been significantly altered with the lower receiver at the front of the gun removed. It appears to have been replaced by the recoil spring assembly cover which appears to slot into the receiver. Sadly, we didn’t have time to disassemble the N4 to examine this.

The N4’s bolt assembly also has more serrations, in a slightly different orientation, on its bolt assembly gripping area, but still no charging handle as recommended on the N2’s tag. The ejection port on the blued prototype is also at a position closer to 12 o’clock when compared to the N2s.

Right side 2 Winchester SMG prototypes — Right side profile view of the two prototypes with their stocks deployed (Matthew Moss)

The N2 has a metal trunnion block, that the recoil spring guide rod screws into, this is held in place within the receiver by a cross pin. The bolt appears to be removed through the rear of the receiver once the stock assmbly/end cap is removed and the bolt assembly freed.

The folding stock was retained by spring tension of the wire metal stock against a wingnut-shaped catch that is riveted onto the recoil spring assembly cover. The stock is locked by a spring loaded push button system similar to the MP40s, this is not particularly sturdy. The shape of the wire stock itself is reminiscent of the US M3. When folded the butt of the wire stock acts as a front grip, the retention of the stock is surprisingly strong and stable.

Intriguingly, the Winchester Museum inventory notes that the guns are designated the N-1 and N-2, with an additional wooden model of the ‘Nato Burp Gun’ being transferred along with a box of duplicate parts in steel for the N2’s aluminium parts.

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Specifications:

Calibre: 9x19mm
Action: Blowback
Overall length: ?
Barrel length: 7.5 inches
Weight empty: ?
Magazine capacity: 33 rounds

Bibliography:

Winchester Repeating Arms Company: Its History & Development from 1865 to 1981, H. Houze (1994)

My thanks to the Cody Firearms Museum at the Buffalo Bill Center of the West for allowing me to examine and film the Winchester submachine gun prototypes. Special thanks to the CFM’s assistant curator Danny Michael for helping disassemble the N2.

All photographs taken by Matthew Moss, courtesy of the CFM & the Buffalo Bill Center of the West. Please do not reproduce photographs without permission or credit.

©The Armourer’s Bench 2018

Steyr AUG Para 9x19mm Submachine Gun

The Steyr AUG or Armee Universal Gewehr (Army Universal Rifle), is one of the earliest Bullpup military issued rifles (if not the earliest) adopted by a military, i.e. the Austrian Military as the Stg77 in 1977. Other early bullpups being the British L85 (SA80), and the French FAMAS. The AUG went on to be adopted by the Australian military and eventually licence built there as the Austeyr F88, the New Zealand Defense Forces, Irish Army, and various other military and police forces worldwide.

In 1990, Steyr developed the first variant of the AUG/9mm Carbine and a 9mm conversion for the AUG-A1 rifle. The conversion consists of a new bolt group, barrel and magazine-well insert. The AUG/9mm Carbine uses the standard 25 round or 32 round magazines from the Steyr MPi 69/81 submachine gun series which is also a Steyr product. Whilst the conversion of standard rifles with the conversion kit is perfectly viable there were difficulties with the standard ejection port due to fired cases rebounding back into the action and also striking the firer!

The 9mm conversion ‘kit’ was replaced with the second variant of the ‘dedicated’ AUG Carbine in 9mm with an improved magazine-well adapter and an ejection-port shield or barrier, this could also be retrofitted on existing 5.56mm housings as an improved conversion kit including an ejection-port shield. However, in 1995 a dedicated AUG /9mm Carbine was introduced with the ejection-port shield molded as an integral part of its stock/housing (the marketing of the 9mm conversion kit being discontinued).

The latest iteration of the weapon the Steyr AUG A3 XS, note the lack of ejection port on the left side and the picatinny optics mounting rail (source)

The AUG/9mm Carbine the barrel does not have a flash suppressor, but has a threaded section behind the muzzle to allow the mounting of aftermarket suppressors etc. The barrel mounts exactly the same as the 5.56mm barrel but does not have a gas tappet system as the 9mm carbine functions as a closed-bolt, blowback. The bolt of the 9mm variant is integral with what is normally the bolt carrier in the standard AUG, the bolt face is machined directly in the bolt carrier face.

AUG PARA1 — Belgian Federal Police officer with AUG SMG with ejection port case deflector (source)

Users of the 9mm variant are mostly police or security forces, notably the Kuwaiti Military Police fielded the 9mm SMG/carbine for some time until surplused a few years back. Ironically the 9mm SMG/carbine is fielded by the Belgian Federal Police whilst the Austrian Gendarmerie used to field the FN (Belgium) manufactured UZI!

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Specifications:

Calibre: 9x19mm
Action: Blowback
Overall length: 61cm (24 inches)
Barrel length: 32.5cm (12.8 inches)
Weight empty: 3kg (6.6lbs)
Magazine capacity, rounds 25 or 32 round box magazines
Cyclic rate: ~700 rpm

Bibliography:

Sub-Machine Gun: The Development of Sub-machine Guns and Their Ammunition, M. Popenker and A.G. Williams (2011)

Steyr AUG Submachine Gun Manual, Steyr, (1990)

The Micro UZI

This week Vic brings us both a video and blog on the Micro UZI

The Micro UZI was an oddball in the UZI family, it was derived from the UZI Pistol which was itself born of an idea to get another IMI product introduced into the US civilian marketplace after the success of the full size UZI carbine by the then importer Action Arms. To get around, or at least comply with the strict US BATF regulations as to what a pistol constituted, a miniaturised variation of the full size UZI was proposed. It had to have the ‘look’ of an UZI but be manageable to handle and shoot with one hand. This required more work than had been involved in the development of the Mini UZI.

The pistol had to have a closed bolt and only fire semi-auto, no buttstock could be fitted on the pistol as this would contravene BATF regulations. The bolt was based on the Mini UZI bolt and the striker but redesigned to be more compact to fit the much shorter receiver. A blocking catch similar to the then recently released model ‘B’ UZI Carbine, was fitted to the bolt. This was a safety device that prevented the gun firing ‘out of battery’. The receiver was the same height and width as all the other UZI family but considerably shorter. To reduce weight the receiver stampings were of 1.5mm material and not 2mm as per the full size & Mini UZI.

The UZI pistol was introduced onto the civilian market around 1984. It eventually was sold in the following calibres: 9mm, 9x21mm (Italian market), .41 AE, and .45 ACP.

Argentine Special Forces. — A joint service special forces team member from Argentina, with a Micro Uzi, posts security during a multinational amphibious beach assault training exercise in Ancon, Peru, July, 2010. (source)

In 1985 IMI realised that the UZI Pistol could be modified to be a compact and effective SMG. To convert it to full-auto fire the lower lip of the bolt which was milled off during manufacture of the semi-auto pistol was left in place. The selector block on the trigger assembly was removed and a folding stock, which was smaller than the Mini UZIs was fitted. The open ‘U’ notch rear sight from the pistol was replaced by a traditional ‘peep’ sight, and finally the barrel from the pistol was lengthened to 5.25″ and compensator notches milled into it to reduce muzzle flip and help control the gun whilst firing. The Micro UZI had a phenomenally high rate of fire at 1,800 rounds per minute, hence most guns were fired in semi-auto only (note that the example I filmed has the selector ‘blocked’ to prevent full-auto selection)!

It is also interesting to note that the Micro UZI was the first gun in the UZI family that started off as a semi-automatic gun and became a full-auto one!

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Specifications:

Overall Length: 46cm / 18 inches
Length (with stock folded): 25cm / 9.8 inches
Weight: 1.5kg/ 3.3 lbs
Action: blowback
Calibre: 9x19mm & various (see text)
Cyclic Rate: 1500-1800 rounds
Feed: 20, 25 or 32-round box magazines

Live Fire: L2A3 Sterling SMG

In this episode we bring you our first live fire and slow motion footage! Matt had the opportunity to fire a British L2A3 Sterling submachine gun and Vic captured some great video. The Sterling was adopted by the British military in 1954 and standardised as the L2A3 in 1956.

Designed by George Patchett, at the Sterling Armaments Company, development began towards the end of the Second World War. After a decade of development and testing the British Army adopted the Sterling. It remained in service into the 1990s and Sterling produced and sold the gun overseas until the company closed in the late 1980s. Licensed versions of the Sterling were made in Canada and production continues today in India.

While the Sterling Armaments Company, the original developers and manufacturer of the gun, produced L2A3s for the government and the commercial market most of the British Army’s Sterlings were made by the government owned Royal Ordnance Factory in Fazakerly near Liverpool.
The gun featured in the video is a Fazakerly-made British Army L2A3, the magazine is also of the slightly simplified government pattern.

slow motion Sterling smg — Frame from the slow motion footage showing a spent 9x19mm case being ejected from the L2A3 (TAB)

In this episode we look at the firing cycle of the L2A3 and how the weapon works. The Sterling uses a standard blowback action and this footage shows it firing in semi-automatic. We can see the breech block travel forward, strip a round from the magazine and chamber it. The round is fired and the breech block then travels rearward again before repeating the cycle.

In future videos we will discuss in-depth the design, development and history of the Sterling.

We would like to thank Graham over at www.slomocamco.com for the loan of the brilliant slow motion camera which captured this great footage!

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F1 Submachine Gun

The Australian military adopted the F1 submachine gun in 1962, with the first guns reaching troops in April 1963, it replaced the venerable Owen gun. Like the earlier Owen the F1 had a top-mounted magazine – a position that lent itself to prone firing and more comfortable carrying when slung. But it also shared some similarities with the British L2A3 Sterling.

NUI DAT, VIETNAM, 7TH BATTALION, THE ROYAL AUSTRALIAN REGIMENT (7RAR) with F1 SMG — Men of the 7th Battalion, The Royal Australian Regiment demonstrate the F1 to the Australian Army Minister, Malcolm Fraser, in Vietnam in 1967 (Australian War Memorial)

The F1 entered service alongside the Australian L1A1 (self-loading rifle/FN FAL), it shared the rifles butt plate and pistol grip – slightly minimising additional unique parts needed by the submachine gun. Australian Ordnance had begun searching for a replacement for the ageing Owen gun after the Korean War. The Owen had been made quickly and cheaply during the Second World War and while it was well liked by Australian troops it was felt it could be improved upon. Maintenance of the older Owen guns proved difficult as each weapon had been hand fitted to speed up production and some parts proved not to be interchangeable.

F1 SMG (Matthew Moss) — Left side view of an Australian F1 submachine gun, from the 1970 production run (Matthew Moss)

A number of designs were developed including one designated the ‘Kokoda’ (presumably after the Kokoda Trail campaign fought by Australian troops in 1942). This design was lighter than the Owen but suffered from overheating problems. A series of designs from the Australian Design Establishment, designated the ‘X’ series, were then developed. These weapons incorporated elements from both the Owen and the British Sterling. Including the Sterling’s perforated barrel jacket and magazine and the Owen’s bolt, magazine orientation and forward pistol grip – a feature many troops with experience with both the Owen and F1 lamented to loss of with the adoption of the F1. The first two ‘X’ series weapons developed into the X3 which in 1962, after successful trials, became the F1.

8RAR with F1 SMG (AWM) — Member of 8th Royal Australian Regiment stood too with his F1 SMG (Australian War Memorial)

The F1 used a standard blowback action with a non-reciprocating charging handle. The charging/cocking handle was positioned on the left side of the receiver with its slot protected from the ingress of dirt by a dust cover. The F1 has a two-position fire selector with up for ‘safe’ and down for ‘fire’. The trigger mechanism allowed for firing single shots by pulling the trigger to the half-way point, this allowed the sear to trip into the semi-automatic position (see the diagram below).

Semi-Auto sear position in F1 SMG — Diagram from Australian Army Parts List showing how the F1’s semi-automatic mode works (source)

Chambered in 9x19mm, the F1 fed from a 34-round curved magazine, although it could use straight, single-feed, Sten or Owen magazines. In the 1960s, in order to achieve commonality with Britain and other Commonwealth nations, that used the Sterling Submachine Gun, the Australian government contacted the Sterling Armaments Company to enquire how much a license to produce Sterling’s magazines would cost, only to be quoted an exorbitant fee. The Australian government were unwilling to pay for the license and produced them anyway. And as Sterling could not afford to take legal action were able to continue to do so – with the understanding they would not sell any commercially. The Australian government would later purchase a number of suppressed Mark 5 Sterling-Patchetts, also adopted by the British army as the L34A1.

The weapon’s ejection port was located on the bottom of the receiver ahead of the trigger guard. A small piece of metal was added in front of the ejection port, as a hand stop, to prevent the operator from inadvertently moving their hand over the port. The F1 had an in-line stock fitting into the rear of the tube receiver. The sights were offset to the right, the rear peep sight folded against the receiver when not in use while the front sight, rather than over the muzzle, projected from the right side of the magazine housing. The F1 could also mount the L1A1 self-loading rifle’s standard L1A2 sword bayonet.

Australian Sailors with F1 SMG — Australian sailors aboard the destroyer HMAS Duchess wait to take part in a live firing exercise with their unloaded F1 submachine guns, c.1969. (Australian War Memorial)

The F1 weighed just over 7lbs (3.2kg), was 28 inches long and had a cyclic rate of approximately 600 rounds per minute. It had a solid butt stock, unlike the Sterling which had a folding stock. The F1 was produced solely by the Lithgow Small Arms Factory with most sources suggesting 25,000 were produced for the Australian military between 1963 and 1973. The Lithgow Small Arms Factory Museum were kind enough to look into the exact number made for us, and reported that there is some uncertainty surrounding the exact number produced with production report totals varying, giving a total of either 21,916 or 24,828.

The F1s saw extensive service in Vietnam and later with Australian peacekeeping troops through to the 1990s. It was issued to rear echelon troops, ACP and aircraft crews and to infantry sections. While the F1 was appreciated for its reliability, for those troops who had experience with the venerable Owen Gun, the F1 lacked a certain something. Colonel Warren Feakes noted that “every time I picked up an F1 I had the feeling that something was missing.” Another Australian veteran, Warrant Officer Kevin Konemann, who served in Vietnam in 1966-67, recalled: “It was awkward to fire from the shoulder and more awkward to fire from the hip” and that “the F1 wasn’t popular. Soldiers found it more difficult to point and bring on target than the OMC [Owen Gun] and firing from the shoulder… was decidedly more difficult without the front hand grip.”

Despite the shortcomings identified by some troops the F1 remained in service alongside the L1A1 self-loading rifle into the early 1990s, when both were phased out of use as the 5.56x45mm F88 (Steyr AUG) was adopted.

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Technical Specifications:

Length: 28 inches (71cm)
Weight (unloaded): 7lbs (3.2kg)
Barrel Length: 8.35 inches (19.8cm)
Action: Blowback
Calibre: 9x19mm
Feed: 34 round box magazine
Cyclic Rate: ~600 rpm

Bibliography:

1966 Infantry Training Pamphlet, Platoon Weapons, Sub-machine Gun 9mm, F1, Australian Army, (source)

Repair Parts Scale, 9mm, F1 SMG, Australian Army, (source)

Vietnam ANZACs Australian & New Zealand Troops in Vietnam 1962-1972, K. Lyles (2004)

Military Small Arms of the 20th Century, I. Hogg & J. Weeks (1985)

‘Another Australian Native: The 9mm F1 Submachine Gun’, Arms & Militaria Collector No.21, pp. 53-56, I. Skennerton, (source)

Modern Small Arms, F. Myatt (1979)

The Owen Gun, W. Wardman, (1991)

F1 Sub-machine Carbine, Lithgow Museum, (source)

Please do not reproduce photographs taken by Matthew Moss without permission or credit. ©The Armourer’s Bench 2018.

Hybrid Sten

During our first research trip last spring I had the opportunity to examine an unusual ‘hybrid’ Sten submachine gun. The weapon combined a MkII Sten’s receiver with a MkIII’s magazine housing. Added to this was a proprietary folding stock and a new fire control group and pistol grip.

Very little is known about the hybrid Sten with Peter Laidler’s book The Sten Machine Carbine mentioning it and the later Osprey book by Leroy Thompson sharing a photograph and brief caption which calls it an “experimental version of the Mk III.” It is also unclear exactly when it was built.

Below are some photographs I took of the Sten, lets look at some of the interesting features of the Hybrid Sten.

left side of the Sten with the stock folded flush under the receiver (Matthew Moss)

No production Variant of the Sten was fitted with an under-folding stock, the Australian Austen, however, directly copied the MP38/40. The entire weapon is covered by a layer of textured, crackle paint finish, this was commonly used on commercial Sterling Mk4 submachine guns. The weapon has a short, 3.5 inch, perforated fore-end welded onto the front of the tube receiver that appears to be from a Lanchester.

Rear right of the weapon close up of its pistol grip, stock and trigger housing (Matthew Moss)

The under folding stock is rudimentary but effective, the butt plate swivels free but the lock up is quite secure. It uses the receiver main spring-loaded return-spring cap. The folding stock attaches to the pistol grip assembly (which can be seen detached below).

The proprietary rectangular trigger group housing brazed onto the tub receiver is unlike any other Sten and lacks a fire-selector.

Left side of the Sten with its pistol grip and stock assembly detached (Matthew Moss)

The pistol grip itself is made from paxoline, a form of early resin plastic. The shape shape of the pistol grip does not resemble any production or prototype Sten grip. A simple hand-stop, made from a bent piece of sheet metal, has also been added in front of the weapon’s ejection port to prevent the user’s hand moving back and fingers being caught if gripped by the forend.

Right side of the Sten with its stock unfolded (Matthew Moss)

While the origins of the hybrid Sten remain unclear I don’t believe it was an officially made prototype. While impressive it is relatively crudely assembled and does not match the Sten prototypes made by Enfield, such as the VI. Intriguingly, the magazine housing of the weapon has been stamped ‘PILOT’ below the usual ‘STEN MkIII’ stamp. I suspect that the weapon may have been put together by a unit armourer, perhaps authorised by a superior officer to suggest improvements or as an unofficial project gun.

UPDATE: Their is some evidence emerging that this Hybrid Sten may be related to the T42 Sten prototype, part of the Sten MkIV development program. Where this hybrid fits into the story is not yet clear but the similarities are striking, when we have more information we will revisit this weapon.

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Technical Specifications:

Length (with stock folded): approx. 40cm (30in)
Weight: approx. 3kg (7lb)
Barrel Length: 16cm (6.5in)
Action: Blowback
Calibre: 9x19mm
Feed: 32 round box magazine
Cyclic Rate: approx. 500 rpm

Bibliography:

The Sten Machine Carbine, P. Laidler (2000)

The Sten Gun, L. Thompson (2012)

Please do not reproduce photographs taken by Matthew Moss without permission or credit. ©The Armourer’s Bench 2018.

FAMAE PAF Submachine Gun

The 1960s and 70s saw Chile was racked by political turmoil with a military junta, led by General Augusto Pinochet, taking control in September 1973. Pinochet’s Junta took control of the country via a bloody coup, overthrowing President Salvador Allende, and as a result all export of small arms from Britain to Chile ceased. In the early 1970s, before the coup d’etat, The records of the Sterling Armaments Company show Chile purchased an example of the company’s Mk4 submachine guns and no less than 101 suppressed Mk5 Sterling-Patchetts.

With the import of small arms from the UK and other countries banned by an embargo Chile’s government were eager to increase their self-sufficiency. As a result in the mid-1970s the state-owned firearms manufacturer Fábricas y Maestranzas del Ejército (FAMAE) experimented with copying the Sterling Mk4 in an effort to minimise development costs.

Left-side view of the PAF with its stock extented (Matthew Moss)

The resulting 9x19mm submachine gun was dubbed the PAF or ‘Pistola Ametralladora FAMAE’. It took the basic Sterling design and simplified it. The PAF lacks the Mk4’s perforated barrel jacket and instead has an exposed barrel, tipped with a rudimentary spoon-shaped compensator. It also lacked the Sterling’s folding stock, instead it had a simple collapsing stock. As a result, the disassembly catch has been moved 90-degrees to the left side of the receiver.

Right-side view of the PAF (Matthew Moss)

Like the original, the Chilean copy retained the dirt-clearing grooves cut into the weapon’s breech block. The PAF’s plastic charging handle and butt stock shape are reminiscent of the Heckler & Koch MP5 – although much cheaper feeling in quality. The profile of the PAF’s pistol grip is slightly different but the weapon still fed from standard 34-round Sterling magazines. Interestingly, unlike the Sterling’s screwed-in-place barrel, the PAF’s was held in place by a machined barrel nut – in terms of production this is a much simpler system, no doubt borrowed from the Uzi.

left-side view of the PAF with stock collapsed (Matthew Moss)

Mag housing, front sight hood and barrel nut (Matthew Moss)

Magazine Housing (Matthew Moss)

The Chilean copy weighs significantly less than the British original, 2.5kg (5.5 lbs) and reportedly has a much higher 800 rounds-per-minute rate of fire. In general the PAF looks much like Sterling’s own later Para Pistol model, the Mk7.

Some sources suggest that only a small number of toolroom prototypes were made, although the relatively high serial number, #00748, of the example we looked at may indicate a limited production run may have been produced. It is clear, however, that the PAF did not go into general production. Instead, FAMAE later focused on weapons derived from Swiss small arms including the SIG SG 510 and SIG SG 540, and the SAF submachine gun introduced in the 1990s.

Note: The PAF was the last weapon we filmed during this particular research trip and we did not have time to film or photograph the PAF’s internals (we filmed a lot of videos that day and were pressed for time). Rest assured if and when we get the opportunity we will update this article with photographs of the weapon disassembled!

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Technical Specifications:

Length (with stock collapsed): approximately 44cm (17in)
Weight (unloaded): 2.5kg (5.5lb)
Barrel Length: 17.5cm (6.9in)
Action: blowback, open bolt
Calibre: 9x19mm
Feed: 34-round box magazine
Cyclic Rate: suggested ~800 rpm

Bibliography:

The Guns of Dagenham, P. Laidler & D. Howroyd, (1995)

‘The PAF: Chile’s First Indigenous Submachine Gun’, TFB, R. Olive (source)

Please do not reproduce photographs taken by Matthew Moss without permission or credit. ©The Armourer’s Bench 2018.

AUSTEN Submachine Gun

At the beginning of the Second World War the Australian Army, much like Britain, lacked a standard issue submachine gun. Following Britain’s lead a small number of Thompson submachine guns were ordered for trials purposes in early 1941. The Australian military eventually purchased 18,382 Thompson M1928A1s, however, it was realised that an indigenously produced weapon was needed.

1941 saw extensive testing and development of Evelyn Owen’s submachine gun, at the same time technical drawings for the Sten arrived from Britain. The Australian engineers that examined the Sten believed that it was too rudimentary for Australian needs. In September 1941, the Melbourne-based Die Casters Ltd. were contracted by the Ordnance Production Directorate to investigate improving the Sten. W.T. Carmichael & Sons Ltd were also interested in producing submachine guns and both Carmichael and Die Casters were contracted to produce the improved Australian Sten gun.

6534523 — Austen-armed Paratrooper from the Australian parachute battalion training centre, c.1945. The Austen’s folding stock made issue to paratroops one of the few roles that the Austen was better suited to than the Owen gun (AWM)

The Austen was based upon the MkII Sten, however, substantial changes to the design were made. These included a new folding stock based upon the German MP38/40 stock, an added forward pistol grip and a cocking handle slot which ran almost the full length of the tub receiver. This longer slot opened allowed greater ingress of mud and dirt. The most significant internal change was the use of the MP40’s bolt and telescoping return spring. The magazine housing was die cast while the rest of the weapon’s parts were stamped steel. Some aborted attempts by Die Casters Ltd to incorporate die casting production methods lead to early failures but by early 1942 the weapon was ready for production.

307-1 — A close up of the Austen’s Diecast magazine housing (RIA)

Like the Sten, the Austen was a simple blowback submachine gun, chambered in 9x19mm and feeding from a 32-round magazine which fed horizontally from the left. With its stock folded it was 52cm long and weighed 3.9kg (8.8lb) unloaded. By contrast the heavier but more reliable Owen weighed 4.2kg (9.3lb). The Austen’s fixed rear aperture sight was fixed at 100 yards.

The new folding stock increased the weight of the Austen, it was also slightly longer than ideal in order for the butt plate to clear the forward handgrip. Some troops complained that this made the weapon’s length of pull too long. In general the Austen required more parts and was more expensive and complex to manufacture. Some Sten parts were interchangeable with the Austen, as were Sten magazines. Like the Owen it appears that at least some Austens were fitted with suppressors similar to that of the Sten MkII(S) and MkVI.

4122849 — The photograph above shows Lt.Colonel Tucker, commanding officer of the 2/23 Infantry Battalion, testing a suppressed Austen in Borneo in September 1945. Note also the suppressed Owen Gun in the background (AWM)

As Australia was in desperate need of submachine guns both the Owen and Austen were ordered into production. The Austen, however, suffered from a series of delays and quality control issues. As a result only 2,100 Austens had been issued, out of over 16,000 made, to troops by early 1943. In total 19,914 Austens are thought to have been built, most of these were factory spray painted with a camouflage pattern (see image #3) In contrast 45,400 Owen guns were produced by June 1945. The Owen was certainly favoured by troops in the field. A report written following troop trials with 300 Austens noted that the weapon’s working parts were exposed, it didn’t function as well as the Owen after submersion in mud and water, it lacked a flash-hider, its stock was too long and was less accurate than the Owen. The Owen, while heavier, was appreciated for its reliability, ergonomics and balance.

4091565 — Australian women war workers pose with an Austen (AWM)

Attempts were made to produce an improved MkII Austen, which used more die cast parts, however, this was not adopted and only 200 were made. By the end of the war the Austen had been removed from frontline service and placed in reserve. Dutch troops in the Dutch East Indies (present day Indonesia) also used a number of Austens during the Netherlands’ period of decolonisation in the region between 1945-1949. The Owen Gun continued to be used into the 1960s, seeing action in Korea, Malaya and Vietnam before it was replaced by the F1 submachine gun.

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Technical Specifications:

Length (stock unfolded): 73cm (29in)
Weight (unloaded): 4kg (8.8lb)
Barrel Length: 20cm (7.8in)
Action: Blowback, open bolt
Calibre: 9x19mm
Feed: 32-round box magazine
Cyclic Rate: ~500rpm

Bibliography:

‘Australian SMGs During WWII’, The Armourer, K. Driscoll

The Sten Gun, L. Thompson (2012)

Owen and Austen – The WW 2 ‘Aussie’ Machine Carbine Story, G. Barber, (source)

The Owen Gun, W. Wardman, (1991)