Military Rifles 
1894-1960
Military
Semi-auto rifle
Ag m/1942
Military & FSR Rifles
1960-2019
Military Rifles
1990-2019
 

CG 63, CG73 & CG80 FSR

Psg 90

Ag 90  (Barrett 82A1)

Anti Tank Rifles

 

The development of the Ljungman semi-automatic rifle Ag m/42.

Text and pictures by O. Janson

Uppdaterad 2019-04-18

Above the early Swedish Semi-automatic rifle Ag m/1942

Above is  Ag m/1942B.

 

Around 1890 several famous men like Hiriam Maxim, John Moses Browning, Von Mannlicher had brought out ideas for so called automatic rifles. An automatic rifle is actually a self loading rifle. In appearance, general design, size and weight it looks like an ordinary military manually repeating rifle. However the military worldwide was not really interested in self loading rifles. They were happy with their bolt rifles, which were strong and reliable. The military considered at that time negative to use firepower by plenty of shots. They wanted the soldiers to spare their ammunition.

During the Great War there were some attempts to introduce these self loading rifles made by France and Russia.

 

At the end of the war there was however great a demand among the soldiers at the front for semi- or full automatic rifles. A very popular gun was the Winchester M1907 which was purchased privately.

Winchester M1907, with  an extended magazine for the war in France.

 

 

The only military accepted automatic rifle which was used successfully during the Great War was the US BAR, constructed by John Moses Browning. However it was quite heavy.

 

 Between the wars both USA and the Soviet Union accepted semi-automatic rifles.
USA accepted 1936 John Garands semi-automatic rifle. He applied for patent for it already on the 21st of April 1930

 

  John Garands semi-automatic rifle.

Here is one of the patent drawings

 

 

 

 

The Soviet Union and the Red Army made several tests between 1931 and 1936. Sergey Simonov brought out an automatic rifle which was adopted as Model 1936 or AVS-36 in short. Service life of this weapon was relatively short, as it was too complicated and not sufficiently reliable in harsh conditions.

 In 1938 the SVT-38 (Samozaryadnaya Vintovka Tokareva - Tokarev Self-loading rifle) was adopted. It was designed by Fedor Tokarev. 1940 it was improved and adopted as SVT-40. More than 1 million rifles were made prior to 1945.

 

Here is a Tokarev SVT-40

 

  Many enemy troops  like the Finnish and German considered it to be very good, while it has low reputation among Russians. The truth is the matter of training and education. The majority of the Red Army lacked the proper education and training for this nice rifle. They were not capable of taking it apart properly and keeping clean. They preferred the standard Mosin-Nagant bolt action instead.

 The interesting feature of the SVT is that the gas block, along with front sight base and a muzzle brake, was produced as a single barrel extension unit. This enhances the capacity for precision shots. The construction simplified the manufacture of the barrel, but the barrel extension itself unit was quite complicated to make.

 

Test model FM 40 WBG
Eric Wallberg tried to change already existing bolt action
of the Swedish rifle m/39 (Kar 98k) to semi-automatic
(Picture taken at Vapenmuseet in Eskilstuna.)

 

The beginning.

In Sweden the interest for a semi-automatic rifle started around 1938. To start with Eric Wallberg at KATF (Kungliga Armétygförvaltningen, Stockholm) tried to change already existing bolt action rifles to semi-automatic. Very soon it was clear that a completely new construction was needed. An offer went out to constructors. Several guns were tested. They can be seen on the picture.

An interesting construction was made by the Finnish Captain Pelo.
The system used was short recoil operation. This system is very reliable but tends to be heavy due to the construction.

 

One of the weapons from Captain Pelo from Finland.

 

Here is a picture of different test weapons used to develop semi-automatic rifles. I took the photo in Vapenmuseet, Eskilstuna while it still was available to the public. Unfortunately it is closed now.

 

Click on the picture to make it larger. (260 Kb)

 

Ag m/42 (Ag = Automatic Rifle)

Swedish terminology calls semi-automatic rifles for automatic rifles although they are only semi-auto. Full automatic weapons are called Kulsprutegevar (Light machinegun) or Kulsprutepistol (Submachine gun).

Development

The winner of this contest was a construction made by manager Erik Eklund at AB J.C. Ljungmans engineering company (LME) in Malmo.

The first meeting about this rifle was held 25th of August 1941 and the semi-automatic rifle was accepted on the 5th of December 1941.

 It was also here the test rifles were built. This company normally produced pumps for petroleum. The construction has borrowed some ideas from the Tokarev SVT-38. The Swedish gas system is inferior to the Russian because the gas tube and the barrel are locked together and when the barrel becomes warm it can note move properly because of the gas tube.

The influence on dispersion of heating of the barrel during continuous firing wary from best results 83 mm at 100 m to the worst case with 356 mm at 100 m! The SVT-38 and 40 don’t have this problem because of the muzzle attachment with the gas chamber. The semi-automatic rifle was called Automatic Rifle m/42 (Ag m/42) and it  was introduced to the Swedish Army less than one year after having left the drawing board, extraordinary by any standards. 

The manufacturing of Ag m/42 took part in Eskilstuna at Carl Gustaf’s gun factory during basically only 1943. All together 30 000 Ag m/42 were made. The instruction manual was first issued to the military separately but from 1943 edition of Instruction for the soldier this manual was included. The manual remained as part of this Instruction for the soldier until 1970.

 

The "Problem Child" Ag m/42

There were plenty of problems with the Swedish semiautomatic rifle Ag m/42. It caused them many problems, even to the degree it was called the “Problem child” or the “Black Sheep”. One of the major problems was the extractor which broke off too often.

 Engineer Elias Hermelin, was for many years manager of the lab in Carl Gustaf Gunfactory. He wrote following about Ag m/42:

 Considering the delivery of material autumn 1941 (according to the suppliers recommendation) there is a change between the material and the heat treatment which demands a reconstruction.

 28th of April 1942 - material ordered according to suppliers recommendation change of heat treatment in order to try to save from the beginning the unsuitable material.

 

1st of April 1943 broken extractor after hardly 4.000 rounds fired, which caused another change of heat treatment.

In middle of April the new treatment has been applied for the first 50 guns. 13.400 rounds have been fired without malfunction.

30th of April 1943 – 22.900 rounds fired.

During the early summer 1943 changes in the heat treatment between GF and LME.

1st of September 1943 – 8 extractors were found broken. 14.000 extractor were delivered – extensive material testing for hardness was made. Limit for scraping was decided by shooting.

In the beginning of September 1943 it was found out that LME had delivered extractors with changes in the hardness index. The steel from Fagerstad Steel had a great variations of carbon from 0.15 – 0.40%.
This was a strange failure by a company, who’s chief engineer at Fagersta Company 1882 – 1903 was Johan August Brinell. The man who set the standard for testing steel hardness!

September 1943 – New tests showed good results. New material with C= 0.70% have been delivered to LME. The older material with C= 0.20% should be used for other parts in the work.

16th November 1943 – First delivery from LME of extractors in the new material didn’t arrive to Gun Factory until 17th of April 1944.

----

There were other problems also. The rifles were stowed away in storages and covered with grease. The gas tubes were made of ordinary steel. Gun grease is hydroscopic and collected water, which caused the tubes to rust. This was changed to stainless tubes later. The magazine fell out by mistake sometimes. This was later corrected.

A major refurbish of all Ag m/42 was made in the early 1950s. The result became Ag m/42B. Once apon a time the “Problem Child” had become a rather good service rifle which was used until it was relieved by the assault rifle AK4 (German G3) 1965. The army had the false idea that AK4 should be used instead of Ag m/42 and the submachine gun Kpist m/1945B. Nowadays the Army reconsider their ideas.

 

Above is one of the rare remaining original Ag m/1942

 

original Ag m/1942  (Armymuseum)

 

Function:

The basic feature of the Ljungman Ag m/42 system was unusual, when first introduced, although it has since become more widespread: The usual gas piston assembly has been discarded in favour of a simple direct gas construction, where the gases themselves impinge upon the bolt. There is no gas piston nor any rod device at all used to convert the gas pressure into mechanical action! This direct-gas system has since been used with success on Stoners AR10 and AR15 rifles.

When the bullet passes the hole in the top of the barrel, a small amount of gases are returning backwards through a gas tube. There is a small cup fixed to the carrier of the bolt surrounding the gas tube. When the gases come backward they hit this cup and force the bolt carrier backwards and the bolt is lifted up from its locked place.

 

 

The rear end of the gas tube comes out above the chamber
The rear end of the gas tube meeting the cup on the bolt-carrier.
The rear end of the gas tube meeting the cup on the bolt-carrier. Closed action.
The rear end of the gas tube meeting the cup on the bolt-carrier. Opening action.

Note that there is not any gasket but the steel cup itself.

 

 The simple direct gas construction, where the gases themselves impinge upon the bolt.
(from Army instruction 1969)

 

  The ammunition used by the military from 1894 was a cartridge called m/94 with a 10,1 gram (157 grain) round nose bullet. Since many years before WW2 ammunition manufacturers in Sweden had made torpedo ammunition with a 9 gram (140 grain) bullet for the civilian Sharpshooter association. This torpedo bullet had much better ballistics then the round nose bullet.

1941 the defence forces accepted this bullet and it was called prj m/41.

The rear sights of Ag m/42 had a small picture of either round nose or torpedo to show the soldier how to make his sight according to what ammunition he used. (See the picture below.)

 

The rear adjustable sight

At the arrow you can see the mark for the torpedo bullet prj m/41.

 

The different cartridges in the Swedish 6,5x55 mm in the army manual 1960.

At top of the page it says which weapons can be used with these 6,5x55 cartridges:

Carbine m/94, Rifles m/96, m/38, m/41(B);

ag m/42 B, kg m/21 and m/37;

Machineguns m/14-29, m/36 (ground, AA and tank), m/39 (tank) and m/58.

 

You can clearly see the bullets:

  1. The round nose prj m/94

  2. The newer torpedo bullet prj m/41

(prj shortening of projectile)

 

Improvements.

Major Karl-Olof Björsell (retired) has told me an episode from spring 1951 when his company started to shoot for the first 2-3 shots the guns refused to reload properly. Rust coloured oil came out of the gas tube instead. After these shoots the rifles worked fine. I remember myself that the first time I shot with an Ag m/42B, during my time at the High school, how I was amazed by the puff of air I got over my head for each shot.

 From the beginning the gas tube was made of steel which rusted.

The soldiers found it easy to drop the magazines by mistake

The cleaning rods were from the beginning made of a tube with inner steel rod which should be screwed together to make full length so they could reach all the way. The construction was too weak.

The cover for the bolt carrier, which was used for loading and discharging of the gun, was only serrated. With cold and numb fingers this serration was too little.

 If you consider the very haste with which the Ag m/42 was adopted it is not strange that there was a need for modifications and they were:

 

  1. The gas tube was made of rustproof material.

  2. An extra hook in the front end of the magazine was added beside the original catch on the rifle.

  3. The recoil spring was made out of double wires for extra strength. They are two springs joined by a tube of steel.

  4. The cleaning rod was exchanged for the one used with rifle m/38, which is shorter than the one for the Mauser rifle m/96.

  5. The cover for the bolt carrier was equipped with two round bottoms, one on each side. A recoil buffer of rubber was added to save the empty brass from being bent, when they were thrown out after firing the cartridge.

  6. The trigger mechanism.

  7. Extractor was redesigned.

 

These improvements were accepted 1953. During the first part of 1950:s all the Ag m/42 was improved. This was done so very well that you most likely will never find any original Ag m/42 which has not been improved. They are extremely rare. The improved rifle was called Automatic rifle m/42 B.

 

 

The cover for the bolt carrier on Ag m/42 first model.

 

The cover for the bolt carrier on Ag m/42 B.
The cover for the bolt carrier was equipped with two round bottoms, one on each side.
A
cylindrical recoil buffer of rubber was added to spare the empty brass from being bent, when they were thrown out after firing the cartridge.

 

Ag m/42 magazine (first model)

Ag m/42B  magazine - second model with extra hooks.

 

Automatgevär m/42, Ag m/42
Calibre 6,5×55
Ammunition 6,5 mm m/94
Feed 10-round, double row magazine
Rate of fire semi automatic 
Design Ljungman AB
Action Gas operated, tipping bolt
Manufacturer Carl Gustaf Gun Factory
Year of delivery 1942-1946
Quantity  ≈32000
Barrel 637 mm
Rifling 6 grooves, rh
Length 1217 mm
Weight 4,1 kg
Sights 100-700 m
Miscellaneous Ag m/42 B; improved gas system.
Also made in Egypt as 'Hakim'
Status Obsolete, sold

 

[Top of the page]

Continue reading about Ag m/42B part 2


References:

Karl-Olof Björsell, Gothia Arms Historical Society annual magazine No 14, 1995

Claes-Goran Roos, EVhS

Instruction manuals for the Swedish army 1939 to 1983.

Josef Alm, Arméns eldhandvapen förr och nu, 1953

Vapenmuseet, Eskilstuna Sweden

Joseph E. Smith and W.H.B. Smith 10th Edition of Small arms of the World 1973, ISBN: 0-89104-021-8

Ian Hogg & John Weeks, Military small arms of the 20th century, 1973, SBN 85368 319 0

 


 

Military Rifles 
1894-1960
Military
Semi-auto rifle
Ag m/1942
Military & FSR Rifles
1960-2019
Military Rifles
1990-2019
 

CG 63, CG73 & CG80 FSR

Psg 90

Ag 90  (Barrett 82A1)

Anti Tank Rifles

 

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