Ag m/42
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| Ag m/42 | |
|---|---|
| 300px | |
| Type | Semi-automatic rifle |
| Place of origin |  Sweden
|
| Service history | |
| In service | 1942 - 1960s (Sweden) |
| Used by | See Users |
| Production history | |
| Designer | Erik Eklund |
| Designed | 1941 |
| Variants | Ag m/42B |
| Specifications | |
| Cartridge | 6.5x55mm |
| Action | gas-operated |
| Feed system | 10-round box magazine |
The Automatgevär m/42 (Ag m/42) (outside of Sweden commonly known as the AG42, AG-42 or Ljungman) is a Swedish semi-automatic rifle in limited use by the Swedish Army from 1942 until the 1960s.
History
The Ag m/42 was designed by Erik Eklund of the AB C.J. Ljungmans Verkstäder company of Malmö around 1941, and entered production at the Carl Gustafs Stads Gevärsfaktori in Eskilstuna in 1942. Some 30 000 rifles were manufactured in all for the Swedish Army. This was a relatively small number of weapons and the standard infantry rifle remained the 6.5 mm bolt action m/96 Mauser.
Norwegian "police troops" trained in Sweden during World War II were issued a number of Ag m/42s and brought them with them to Norway when the Germans surrendered in 1945. These rifles were never modified to the later Ag m/42B version. The serial numbers of these weapons were between 22000 and 25000 (see Samlarforum.nu). However, in the Netherlands exists a weapon with serial number 22742 and is a AG m/42B. So, at least one (or more?) did escape.
After a number of issues had been discovered, including a serious problem with rusting gas tubes, the existing stocks of the rifle were modified between 1953 and 1956, and the reworked rifles were designated Ag m/42B. Modifications included a stainless steel gas tube, two knobs on the breech cover, a new elevation knob for the rear sight, a rubber case-deflector, new magazines and new cleaning rod. The Ag m/42B was replaced in Swedish service in the 1960s by the Heckler & Koch G3-derived Ak 4
The Ag m/42B was used as the basis for the Egyptian Hakim rifle, which uses the 7.92x57mm Mauser cartridge. Sweden sold the machinery to Egypt and the Hakim was therefore built with the same machine tools used for the Ag m/42B. Eventually, the Hakim was modified into a carbine using the intermediate-power 7.62x39mm Russian cartridge, called the Rashid or Rasheed.
Operation
The Ag m/42 is operated by means of a direct impingement gas system, similar to that of the French MAS-49 and American M16 rifles. The Ag m/42 also uses a tilting breech block like the Tokarev SVT-38 / SVT-40 and FN FAL rifles.
The Ag m/42 uses the 6.5x55mm cartridge loaded into a removable 10-round box magazine. In practice, however, the magazine usually remains attached to the rifle while it is loaded from the top with five-round stripper clips. Like the British Lee-Enfield and Soviet SVT-40, the Ag m/42's magazine was intended to be removed only for cleaning.
Use caution when firing the Ljungman and Hakim rifles as the burn rate of the powder has a dramatic effect on the operation of the rifle. There have been reported cases of catastrophic failures of both these rifles when fired with incorrect ammunition. Even the Swedish m/41 ammunition was required to be lightly oiled by Swedish troops prior to loading as the burn rate of the powder is too slow and the oiling of the cartridge body facilities extraction.
The main dynamic involves the pressure curve and the timing of the pressure curve as it relates to the location of the gas port in the barrel. While the Hakim has a gas port adjustment the Ljungman does not. As the bullet passes the gas port the gas pressure is channeled back to the bolt carrier to unlock the bolt. With a powder that is too slow a burn rate the bolt carrier opens violently premature and at an extremely excessive pressure. This causes the extractor to tear the rim off the cartridge case exposing the action to the dumping of very high pressures which typically exits the action downward into the magazine well, blowing the magazine completely out of the rifle and often destroying the magazine and stock in the process. Close attention must be paid regarding the use of correct ammunition in these two rifles.
