The M28 Jarmann harpoon rifle was a modification of the Jarmann M1884

Jarmann M1884

The Norwegian Jarmann M1884 was among the first bolt action repeating rifles to be adopted in the Western world. Its adoption, and subsequent modifications, turned the Norwegian Army from a fighting force armed with single-shot black powder weapons into a force armed with modern repeating weapons...

 Norwegian

Norwegian Army

Norway achieved full independence in 1905, and in the first century of its short life has contributed to two major conflicts, the Cold War and the War on Terror. The Norwegian Army currently operates in the north of Norway and in Afghanistan as well as in Eastern Europe. The Army is the oldest of...

 service rifle

Service rifle

The service rifle of a given army or armed force is that which it issues as standard to its soldiers. In modern forces, this is typically a highly versatile and rugged assault rifle suitable for use in nearly all theatres and environments...

.

Between the wars, several Norwegian gunsmiths attempted to create harpoon guns, intended for hunting seal

Pinniped

Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semiaquatic marine mammals comprising the families Odobenidae , Otariidae , and Phocidae .-Overview: Pinnipeds are typically sleek-bodied and barrel-shaped...

s and shooting rescue lines to boat

Boat

A boat is a watercraft of any size designed to float or plane, to provide passage across water. Usually this water will be inland or in protected coastal areas. However, boats such as the whaleboat were designed to be operated from a ship in an offshore environment. In naval terms, a boat is a...

s in distress. Seeing a ready market, and having access to the several thousand Jarmanns in storage, Kongsberg Våpenfabrikk designed a harpoon gun referred to as the M28. As part of the rebuild, the magazine and the repeating mechanism were removed, and the handguard and barrel were shortened. In addition, a heavy rubber shoulderpad was added to reduce the considerable recoil. The rifle could still fire the ordinary 10.15 x 61R cartridge after the conversion. A box could be mounted under the handguard containing up to 300 metres (1000 ft) of thin rope. Kongsberg manufactured the M28 harpoon gun until 1952, when they started using the Mauser

Mauser

Mauser was a German arms manufacturer of a line of bolt-action rifles and pistols from the 1870s to 1995. Mauser designs were built for the German armed forces...

 98

Karabiner 98k

The Karabiner 98 Kurz was a bolt action rifle chambered for the 8x57mm IS/7.92×57mm IS cartridge that was adopted as the standard service rifle in 1935 by the German Wehrmacht. It was one of the final developments in the long line of Mauser military rifles...

 mechanism in a new harpoon gun called the M52. The sources indicate that around 1,911 Jarmann rifles were modified to M28s, about half of them after World War II.

The M28 was advertised as being suitable for use for hunting and rescue work, as well as for general shooting of lines. The advertisement reproduced here specifically mentions its suitability for firefighter

Firefighter

Firefighters are rescuers extensively trained primarily to put out hazardous fires that threaten civilian populations and property, to rescue people from car incidents, collapsed and burning buildings and other such situations...

s, people erecting telephone line

Telephone line

A telephone line or telephone circuit is a single-user circuit on a telephone communication system...

s and general construction work. The M28 was seen as suitable for hunting Northern bluefin tuna

Northern bluefin tuna

The Northern bluefin tuna is a species of tuna in the Scombridae family. It is variously known as the Atlantic bluefin tuna, giant bluefin tuna and formerly as the tunny. Atlantic bluefin are native to both the western and eastern Atlantic Ocean, as well as the Mediterranean Sea...

, seals, swordfish

Swordfish

Swordfish , also known as broadbill in some countries, are large, highly migratory, predatory fish characterized by a long, flat bill. They are a popular sport fish of the billfish category, though elusive. Swordfish are elongated, round-bodied, and lose all teeth and scales by adulthood...

 and other large marine animals. Among the equipment that could be delivered for the M28 were hunting harpoons, rescue harpoons, rocket

Rocket

A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engine. In all rockets, the exhaust is formed entirely from propellants carried within the rocket before use. Rocket engines work by action and reaction...

-assisted harpoons, 'dum-dum bullets

Dum-dum

An expanding bullet is a bullet designed to expand on impact, increasing in diameter to limit penetration and/or produce a larger diameter wound. They are informally known as a Dum-dum or dumdum bullets...

' and rope of various lengths in special crates. The special rounds for launching harpoons were manufactured until the mid-1970s.