.338 Lapua Magnum .338 Lapua Magnum cartridge next to a .338 Norma Magnum Type

.338 Lapua Magnum .338 Lapua Magnum cartridge next to a .338 Norma Magnum Type Rifle Place of origin Finland Service history Used by Multiple official and civil users Wars War in Afghanistan Iraq War Production history Designer Nammo Lapua Oy Designed 1989 Produced 1989–present Specifications Parent case .416 Rigby, .338/416 Case type Rimless, bottleneck Bullet diameter 8.58 mm (0.338 in) Neck diameter 9.46 mm (0.372 in) Shoulder diameter 13.82 mm (0.544 in) Base diameter 14.91 mm (0.587 in) Rim diameter 14.93 mm (0.588 in) .338 Lapua Magnum The .338 Lapua Magnum (8.6×70mm or 8.58×70mm) is a rimless, bottlenecked, centerfire rifle cartridge. It was developed during the 1980s as a high-powered, long-range cartridge for military snipers. It was used in the War in Afghanistan and the Iraq War. As a result of this, it became more widely available. The loaded cartridge is 14.93 mm (0.588 in) in diameter (rim) and 93.5 mm (3.68 in) long. It can penetrate better-than-standard military body armor at ranges up to 1,000 metres (1,090 yd) and has a maximum effective range of about 1,750 metres (1,910 yd) with C.I.P. conform ammunition at sea level conditions. Muzzle velocity is dependent on barrel length, seating depth, and powder charge, and varies from 880 to 915 m/s (2,890 to 3,000 ft/s) for commercial loads with 16.2-gram (250 gr) bullets, which corresponds to about 6,525 J (4,813 ft⋅lbf) of muzzle energy. British military issue overpressure .338 Lapua Magnum cartridges with a 91.4 mm (3.60 in) overall length, loaded with 16.2-gram (250 gr) LockBase B408 very-low-drag bullets fired at 936 m/s (3,071 ft/s) muzzle velocity. This round, fired from a L115A3 Long Range Rifle, was used in November 2009 by British sniper Corporal of Horse (CoH) Craig Harrison to establish the then- new record for the longest confirmed sniper kill in combat, at a range of 2,475 m (2,707 yd).[4][5] In reports CoH Harrison mentions the environmental conditions at Musa Qala were perfect for long range shooting: no wind, mild weather, clear visibility.[6] In addition to its military role, it is increasingly used by hunters and civilian long-range shooting enthusiasts. The .338 Lapua Magnum is capable of taking down any game animal, though its suitability for some dangerous game (Cape buffalo, hippopotamus, white rhinoceros, and elephant) is arguable, unless accompanied by a larger "backup" calibre: "There is a huge difference between calibres that will kill an elephant and those that can be relied upon to stop one."[7] In Namibia the .338 Lapua Magnum Rim thickness 1.52 mm (0.060 in) Case length 69.20 mm (2.724 in) Overall length 93.50 mm (3.681 in) Case capacity 7.532 cm3 (116.24 gr H2O) Rifling twist 254 mm (1-10") Primer type Large rifle magnum Maximum pressure 420.00 MPa (60,916 psi) Ballistic performance Bullet mass/type Velocity Energy 12.96 g (200 gr) SP 1,023 m/s (3,360 ft/s) 6,734 J (4,967 ft⋅lbf) 16.20 g (250 gr) Partition 921 m/s (3,020 ft/s) 6,875 J (5,071 ft⋅lbf) 16.20 g (250 gr) Lapua Scenar GB488 VLD 925 m/s (3,030 ft/s) 6,925 J (5,108 ft⋅lbf) 19.44 g (300 gr) Sierra HPBT MatchKing 851 m/s (2,790 ft/s) 7,045 J (5,196 ft⋅lbf) 19.44 g (300 gr) Lapua Scenar GB528 VLD 847 m/s (2,780 ft/s) 6,971 J (5,142 ft⋅lbf) Test barrel length: 690 mm (27.15 inches) Haenel Rs9 and R&S SX1 MTR Source(s): Vihta Vuori Powder N570 Lapua (690 mm; 27.15 inches) barrel[1][2][3] is legal for hunting Africa's Big five game if the loads have ≥ 5,400 J (3,983 ft⋅lbf) muzzle energy.[8] History Initial development Final development Law enforcement and military users Cartridge dimensions Supersonic range performance of the .338 Lapua Magnum Performance with C.I.P . conforming cartridges Performance improvement experiments with non-C.I.P .-conforming cartridges .338 Lapua Magnum as a parent case The .300 Lapua Magnum The 7.62 UKM Wildcats See also Notes References External links In 1983, Research Armament Industries (RAI) in the United States began development of a new, long-range sniper cartridge capable of firing a 16.2-gram (250 gr), 0.338-inch (8.6 mm) diameter bullet at 914 metres per second (3,000 ft/s) that could lethally penetrate five layers of military body armour at 1,000 m (1,094 yd). After preliminary experiments, a .416 Rigby case necked down to take a 0.338-inch (8.6 mm) bullet was selected, since this diameter presents an optimum of sectional density and penetrating capability for practical spin- stabilized rifle bullets (bullets up to about 5 to 5.5 calibers in length).[9] The .416 Rigby is an English big game cartridge that was designed in 1911 to accommodate 325 MPa (47,137 psi) pressures. One of the disadvantages of these old cartridge cases, which were intended for firing cordite charges instead of modern smokeless powder, is the thickness of the sidewall just forward of the web. During ignition, the cartridge's base, just forward of the bolt face, is not supported. Contents History Initial development During the process RAI employed Jim Bell and Brass Extrusion Labs Ltd. (B.E.L.L.) of Bensenville, Illinois, to make the .338/416 or 8.58×71mm cartridge cases, Hornady produced bullets, and RAI built a sniper rifle under contract for the U.S. Navy. RAI found that the BELL cases did not fulfill the requirements, since they were modified low pressure .416 Rigby cases. Pressed by military deadlines RAI looked for another case producer and contacted Lapua of Finland in 1984.[10] RAI was forced to drop out of the program due to financial difficulties. Subsequently, Lapua of Finland put this cartridge into limited production.[11] The .338/416 rifle program was later canceled when the contractors were unable to make the cartridge meet the project's velocity target of 914 m/s (3,000 ft/s) for a 16.2 g (250 gr) bullet, due to excessive pressures rupturing cartridge cases. The current .338 Lapua Magnum cartridge was developed as a joint venture between the Finnish rifle manufacturer SAKO and the British rifle manufacturer Accuracy International along with the Finnish ammunition manufacturer Lapua, or more officially Nammo Lapua Oy, which since 1998 is part of the Nordic Ammunition Group (Nammo).[12][13] Lapua opted to redesign the .338/416 cartridge. In the new case design, particular attention was directed toward thickening and metallurgically strengthening the case's web and sidewall immediately forward of the web. In modern solid head cases, the hardness of the brass is the major factor that determines a case's pressure limit before undergoing plastic deformation. Lapua tackled this problem by creating a hardness distribution ranging from the head and web (hard) to the mouth (soft) as well as a strengthened (thicker) case web and sidewall immediately forward of the web. This resulted in a very pressure resistant case, allowing it to operate at high pressure and come within 15 m/s (50 ft/s) of the original velocity goal. Lapua also designed a 16.2-gram (250 gr) .338 calibre Lock Base B408 full metal jacket bullet, modeled after its .30 calibre Lock Base bullet configuration. The result was the .338 Lapua Magnum cartridge which was registered with C.I.P. (Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives) in 1989. With the procurement by the Dutch Army, the cartridge became NATO codified. The .338 Lapua Magnum fills the gap between weapons chambered for standard military rounds such as the 7.62×51mm NATO and large, heavy rifles firing the .50 BMG cartridge.[14] It also offers an acceptable amount of barrel wear, which is important to military snipers who tend to fire thousands of rounds a year in practice. This was achieved by coupling a sensible case volume (7.40 ml) to bore area (56.86 mm2/0.5686 cm2) ratio (13.01 Oratio) with ample space for loading relatively long slender projectiles that can provide good aerodynamic efficiency and external ballistic performance for the projectile diameter.[notes 1] Like every other comparable large magnum rifle cartridge, the .338 Lapua Magnum presents a stout recoil.[15] An appropriate fitting stock and an effective muzzle brake helps to reduce recoil-induced problems, enabling the operator to fire more rounds before getting too uncomfortable to shoot accurately. Good factory loads, multiple projectile weights and factory special application ammunition are all available.[notes 2][16] Due to its growing civilian popularity, several high quality tactical and match (semi) custom bolt actions designed for the .338 Lapua Magnum are becoming available. These (semi) custom bolt actions are used with other high grade rifle and sighting components to build custom sporting and target rifles. Final development The .338 Lapua Magnum cartridge is in law enforcement or military[17][18] use with: Albania: RENEA—Sako TRG-42[19] Australia: Blaser Tactical 2[20][21][22] Bangladesh:Bangladesh Armed Forces-Accuracy International AWM Canada: Canadian Forces—C14 Timberwolf Medium Range Sniper Weapon System (MRSWS)[23] Chile: Chilean Army - APR338 and PGM 338[24] Barrett Model 98B Colombia: TAP .[25] Czech Republic — Sako TRG-42[19] Denmark: Military of Denmark—Sako TRG-42[26][27][28] Estonia: Military of Estonia reconnaissance units and special forces—Sako TRG-42.[26][29] Finland: Finnish Defence Forces—Sako TRG-42 France: French Army, GIGN and Commandement des Opérations Spéciales—PGM 338, Sako TRG-42, AWSM Georgia: Police and military - Accuracy International AWM and Sako TRG series, as well as Satevari MSWP. Domestic analogue .338 GBM produced by STC DELTA[30] Germany: Bundeswehr—Haenel RS9 designated as G29 in service with the special forces; replacing the G22,[31][32][33] Erma SR-100,[34] uploads/Industriel/ 338-lapua-magnum-wikipedia-pdf.pdf

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