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Jarmann M1884: Encyclopedia BETAFree Encyclopedia |
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DescriptionJacob Smith Jarmann designed his first breech-loading rifle—firing cardboard cartridges—in 1838, but this was turned down by the armed forces at the time. The logic was that a rifle capable of firing 13 shots a minute would be impossible to resupply with enough ammunition. In the 1870s, he stepped down from the daily running of his workshop to work on his newly invented bolt-action rifle. According to the patent, three particulars were considered new and unique with the action he had developed:*The extractor, which not only pulled the spent round out of the breech, but also served to limit the bolt's rearward motion. *The design of the rotating bolt handle, which served to lock the bolt to the receiver in the forward position. *The way the extractor was secured to the body of the bolt.Another interesting oddity is that the Jarmann action does not have a separate ejector, but instead relies on the fact that the extractor pushes the spent round down onto the elevator. The resulting friction was enough to safely eject the round from the receiver.
The first Jarmann design was firmly a single-shot weapon, and Jacob Smith Jarmann was reportedly at first unwilling to design a magazine for it. This may explain why the magazine and bolt do not always work well together.
AmmunitionThe aforementioned Norwegian-Swedish committee also designed the 10.15 x 61R cartridge that the various prototypes as well as the service weapon were chambered for. Originally a black powder round with a paper-wrapped lead bullet, it was later loaded with smokeless powder and a full metal jacket bullet. More than 5 million cartridges were manufactured for the M1884, in addition to several thousand specialty cartridges. The following different variations on the 10.15 x 61R cartridge have been identified:*10.15 Ball, rounded tip, lead bullet wrapped in paper, black powder (possibly testing-only round) *10.15 Ball, flat tip, lead bullet wrapped in paper, black powder *10.15 Ball, flat tip, full metal jacket, smokeless powder *10.15 Gallery, round lead bullet (for use indoors or at short ranges) *10.15 Gallery, same as above but with a ring crimped around the neck of the case *10.15 Blank, unpainted wooden 'bullet', smooth case *10.15 Blank, same as above but with six long ridges pressed into the case *10.15 Blank, same as above but with six long and six short ridges pressed into the case *10.15 Dummy, red wooden 'bullet' going all the way to the bottom of the case, six long and six short ridges pressed into the case, and two rings crimped around the neck of the case *10.15 Dummy, as above but with just the six long ridges and rings around the neck *10.15 Dummy, as above but with brown wooden 'bullet' and two rings crimped around the neck of the case (tests only). *10.15 Harpoon round, a blank round crimped shut, used only in the M28 harpoon gun *10.15 Harpoon round, as above but closed with a crimped lid AccuracyThe Jarmann rifle was a remarkably accurate rifle for its time. In 1886, the joint Norwegian-Swedish rifle committee, which had selected the Jarmann, created a list of the ballistic properties of all the rifles tested. It is clear from the list that the Jarmann M1884 was significantly better than the other rifles tested, although in part this must be due to the higher muzzle velocity of the Jarmann.The 10.15 mm bullet fired by the Jarmann was fully enfilading (meaning that the path of the bullet would pass through a man-sized target) up to 438 m (479 yd), and at a range of 600 metres (660 yd) it did not spread more than 61 cm (24 in) with uncoated lead bullets and 46 cm (18 in) with jacketed bullets. This compared very favorably to the Remington M1867, then the Norwegian standard weapon, which was enfilading out to 300m (330 yd) and had a spread at 600m of 96 cm (38 in). In comparison, the Gras rifle displayed a spread of 89 cm (35 in) and the Mauser rifle (presumably a Gewehr 71) had a spread of 80 cm (31.5 in), both at 600m (660 yd). Service
When the weapon was chosen and first issued, the military considered it a very good weapon. It had a good rate of fire and had less than half the spread of the Remington M1867 at 600 m (46 versus 96 cm). It was later eclipsed, however by the radical development of firearms at the time. Within a decade it was phased out and replaced by the Krag-Jørgensen rifle. Even though it was phased out, several second-line units were issued the weapon in 1905, when war between Norway and Sweden was considered imminent. Towards the end of their use in the armed forces, the original gunpowder cartridges were replaced by cartridges filled with smokeless powder. Despite the increase in muzzle velocity, the sights were not altered, thus radically decreasing the accuracy of the rifle. Fate of the JarmannsJarmann M1884s in their original condition are now extremely rare. During the 1920s and 1930s, a number of the surplus rifles was either sold to civilians or rebuilt into M28 harpoon guns.
It is reported that the Germans melted down the last remaining Jarmann rifles in military warehouses during the Nazi occupation, since they were "too obsolete to be of interest, too modern to have lying around".It is quite possible that as many as 21,000 Jarmanns were destroyed in this fashion. M28 Harpoon gunWeapon|is_ranged=yes|name=Jarmann M28 harpoon gun | image= | caption=The M28 was delivered in a custom crate loaded with supplies | nation=Norway | type=bolt action harpoon gun | designer=Jacob Smith Jarmann | design_date=1928 | service=1928 onwards | cartridge=10.15 x 61R rimmed | action=Bolt action | rate=Unknown, but as fast as the operator could reload | velocity= Unknown | range= 300 m (330 yd) | weight= 5.3 kg (11.7 lb) empty, 7.7 kg (17 lb)with harpoon | length= 1.06 m (42 in) | part_length= Unknown | feed= 1 | sights=V-notch and front post | variants=M28 | number=1,911 | |||||||||||||||||||||||||||||||||||||||||||||||
A 1930 advertisement for the M28 |
| Rifle | Jarmann M1884 | Remington M1867 | Mauser Gewehr 71/84 | Gras rifle | Martini-Henry |
| Accuracy at 600 m | 46 cm (18.1 in) | 96 cm (37.8 in) | 80 cm (31 in) | 89 cm (35 in) | 69.5 cm at 1,100 m |
| Enfilading | 438 m (1,437 ft) | 300 m (984 ft) | 350 m (1,150 ft) | 379 m (1,243 ft) | 346 m (1,135 ft) |
| Effective range | 2,400 m (2,620 yd) | 900 m (980 yd) | Unknown | Unknown | 1,370 m (1,500 yd) |
| Rate of fire | Unknown | 13 RPM | Unknown | Unknown | 8 to 12 RPM |
| Magazine capacity | 8 | None | 8 | None | None |
| Calibre | 10.15 x 61R | 12.17 x 44 rimfire | 11.15 x 60R | 11 x 59R | .450/577 (11.455 x 65R) |
| Muzzle velocity | 500 m/s (1,640 ft/s) | 381 m/s (1,250 ft/s) | 430 m/s (1,411 ft/s) | 455 m/s (1,493 ft/s) | 416 m/s (1,365 ft/s) |
| Barrel length | 850 mm (33.5 in) | 951 mm (37.4 in) | Unknown | Unknown | 840 mm (33.1 in) |
| Total length | Unknown | 1355 mm (53.3 in) | Unknown | Unknown | 1245 mm (49 in) |
| Loaded weight | 4.5 kg (10 lb) | 4.32 kg (9.52 lb) | Unknown | Unknown | 3.83 kg (8.5 lb) |
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