Full metal jacket (ammunition)
A full metal jacket (FMJ) bullet is a small-arms projectile consisting of a soft core (often lead) encased in an outer shell ("jacket") of harder metal, such as gilding metal, cupronickel, or, less commonly, a steel alloy. A bullet jacket usually allows higher muzzle velocities than bare lead without depositing significant amounts of metal in the bore. It also prevents damage to bores from hard steel or armor-piercing core materials.
History
[edit]Despite a widespread belief that the full metal jacket bullet was invented ca. 1882 by Swiss Colonel Eduard Rubin while he was working for the Swiss Federal Ammunition Factory and Research Center,[1][2][3][4] in fact it was known already in the 1880s that the actual inventor was Prussian Major (later Lt.-Col.) Julius Emil Bode (1835-1885), who came up with the idea either in 1875 or 1876.[5][6][7][8][9]
The use of full metal jacketing in military ammunition came about in part because of the need for improved feeding characteristics in small arms that used internal mechanical manipulation of the cartridge in order to chamber rounds as opposed to externally hand-reloading single-shot firearms. The harder metal used in bullet jackets was less prone to deformation than softer exposed lead, which improved feeding. That also allowed bullets to withstand much higher velocities caused by the decrease of the caliber.[10]
In addition to the various advantages afforded by FMJ rounds, the Hague Convention of 1899, Declaration III, prohibits the use in international warfare of bullets that easily expand or flatten in the body, so FMJ bullets are effectively mandated by international law as unjacketed, lead bullets do indeed expand in flight and[citation needed] on impact.
Impact characteristics
[edit]By design, fully jacketed projectiles have less capacity to expand after contact with the target than a hollow-point projectile. While this can be an advantage when engaging targets behind cover, it can also be a disadvantage as an FMJ bullet may pierce completely through a target, leading to less severe wounding, and possibly failing to disable the target. Furthermore, a projectile that goes completely through a target can cause unintentional damage behind the target.[11]
See also
[edit]References
[edit]- ^ Huon, Jean (1988). Military Rifle and Machine Gun Cartridges. Alexandria, Va.: Ironside International. ISBN 0-935554-05-X. OCLC 24498827.
- ^ "Swiss Handguns 1882".
- ^ Holt Bobinson (November 2008). "The model 1911 Schmidt Rubin: the other Switzer". Guns Magazine. Archived from the original on 2012-07-15 – via FindArticles.com - CBS Interactive.
- ^ Wood, J. B. (2003). The Gun Digest Book of Firearms Assembly/Disassembly: Centerfire Rifles, Volume 4 (2nd ed.). Iola, WI: Krause Publications. ISBN 0873496310. OCLC 52359378. Archived from the original on 2016-05-07. Retrieved 2015-09-07.
- ^ Archiv für die Artillerie- und Ingenieur-Offiziere des deutschen Reichsheeres (in German). Mittler. 1885.
- ^ "'Das Kleinste Kaliber oder das zukünftige Infanteriegewehr. 1/2' - Viewer | MDZ".
- ^ Monatshefte für Politik und Wehrmacht (in German). 1889.
- ^ "Der" Kamerad Wien, 1862 - 1896: österreichisch-ungarische Wehr-Zeitung (in German). 1887.
- ^ Die Repetir-Gewehre: ihre Geschichte, Entwickelung, Einrichtung und Leistungsfähigkeit; unter besonderer Berücksichtigung amtlicher Schiessversuche und mit Benutzung von Originalwaffen dargestellt (in German). Zernin. 1882.
- ^ Ramage, C. Kenneth (1980). Lyman Cast Bullet Handbook (3rd ed.). Middlefield, Connecticut: Lyman Publications. pp. 27 & 28.
- ^ The Belding & Mull Handbook. Philipsburg, Pennsylvania: Belding & Mull. 1949. pp. 39 & 40.
External links
[edit]- "Declaration (IV, 3) concerning Expanding Bullets". UMN.edu. International Peace Conference at The Hague, which entered into force on September 4, 1900. 1899.
- "European Ammunition Box Translations: FAQ". Rawles.to.
- "Photos showing terminal effects of British Mark 7 .303 bullets". TheBoxTruth.com. 13 June 2014. Archived from the original on 16 July 2011. Retrieved 9 April 2007.