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.50 BMG

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.50 BMG
From left: .50 BMG, 300 Win Mag, .308 Winchester, 7.62x39mm, 5.56x45mm NATO, .22LR
TypeRifle
Place of originUnited States of America
Service history
In service1921–present
Used byNATO and many others
WarsWWII, Korean War, Vietnam War, Cambodian Civil War, Falklands war, Gulf War, War on Terror, Iraq War
Production history
DesignerWinchester Repeating Arms Co. and Frankford Arsenal
Specifications
Case typeRimless, bottleneck
Bullet diameter.510 in (13.0 mm)
Neck diameter.560 in (14.2 mm)
Shoulder diameter.741 in (18.8 mm)
Base diameter.804 in (20.4 mm)
Rim diameter.804 in (20.4 mm)
Case length3.91 in (99 mm)
Overall length5.45 in (138 mm)
Primer type
  1. 35 Arsenal Primer
Ballistic performance
Bullet mass/type Velocity Energy
647 gr (42 g) Speer 3,044 ft/s (928 m/s) 13,144 ft⋅lbf (17,821 J)
655 gr (42 g) ADI 3,029 ft/s (923 m/s) 13,350 ft⋅lbf (18,100 J)
700 gr (45 g) Barnes 2,978 ft/s (908 m/s) 13,971 ft⋅lbf (18,942 J)
750 gr (49 g) Lapua 2,618 ft/s (798 m/s) 11,419 ft⋅lbf (15,482 J)
800 gr (52 g) Barnes 2,895 ft/s (882 m/s) 14,895 ft⋅lbf (20,195 J)
Test barrel length: 45 in (1143 mm)
Source(s): Ammoguide.com

The .50 Browning Machine Gun (12.7x99mm NATO) or .50 BMG is a cartridge developed for the Browning .50 Caliber machine gun in the late 1910s. Entering service officially in 1921, the round is based on a greatly scaled-up .30-06 cartridge. The cartridge itself has been made in many variants: multiple generations of regular ball, tracer, armor piercing, incendiary, and saboted sub-caliber rounds. The rounds intended for machine guns are linked using metallic links.

The .50 BMG cartridge is also used in long-range target and sniper rifles, as well as other .50 machine guns. The use in single-shot and semi-automatic rifles has resulted in many specialized match-grade rounds not used in .50 machine guns. A McMillan Tac-50 .50 BMG sniper rifle was used by Canadian Corporal Rob Furlong to bring off the longest-range confirmed sniper kill in history, when he shot a Taliban combatant at 2,430 meters (2,657 yards) during the 2002 campaign in Afghanistan.[1]

The previous record for a confirmed long-distance was set by US Marine sniper Carlos Hathcock in 1967, the distance was 2,286 meters (2,500 yards) or 1.42 miles (2.29 km). Hathcock used the same round in an M2 Browning Machine Gun equipped with a telescopic sight. This weapon was used by other snipers, and eventually purpose-built sniper rifles were developed especially for this round. The previous standard for ammunition for sniper rifles was .30-06, but the .50 round is more accurate at extreme range.

A wide variety of ammunition is available, and the availability of match-grade ammunition has increased the usefulness of .50 caliber rifles by allowing more accurate fire than lower quality rounds.

History

Power

A common method for understanding the actual power of a cartridge is by comparing muzzle energies. The Springfield .30-06, the standard caliber for American soldiers in World War II and a popular caliber amongst American hunters, can produce muzzle energies between 2000 and 3000 foot pounds of energy (between 3 and 4 kilojoules). A .50 BMG round can produce between 10,000 and 15,000 foot pounds (between 14 and 18 kilojoules) or more, depending on its powder and bullet type, as well as the rifle it was fired from. Due to the high ballistic coefficient of the bullet, the .50 BMG's trajectory also suffers less "drift" from cross-winds than smaller and lighter calibers, making the .50 BMG a good choice for high powered sniper rifles.

Cartridge dimensions

These measurements are not suggested for reloading use.

The 50 BMG 12.7 x 99 NATO has 290 grains H2O (19 ml) cartridge case capacity. The round is a scaled up version of the .30-06 Springfield but uses a case wall with a long taper to facilitate feeding and extraction in various weapons.

50 BMG basic cartridge dimensions. All sizes in inches (in). The common rifling twist rate for this cartridge is 1 in 15 in (381 mm), with 8 lands and grooves. The primer type specified for this ammunition is Boxer primer that has a single centralized ignition point (US and NATO countries). However, some other countries produce the ammunition with Berdan primers that have two flash holes,[2] the U.S. Army Ammunition Data Sheets — Small Caliber Ammunition, not including plastic practice, short cased spotter, or proof/test loads, is 54,923 PSI (378 MPa or 3,787 bar). The proof/test pressure is listed as 65,000 psi (448 MPa or 4,482 bar). As a note these are the military machine gun standards and not ideal for use as guidelines in reloading or personal use.

Military cartridge types

Left to right, rear: Mk211, Spotter, Silver tip (Armor Piercing Incendiary), Blue tip (Incendiary), Black tip (Armor Piercing), SLAP-T, SLAP, Tracer, and Ball.

.50 BMG cartridges are also produced commercially with a plethora of different bullets and to a number of different specifications.

  • Cartridge, Caliber .50, Tracer, M1
Tracer for observing fire, signaling, target designation, and incendiary purposes. This bullet has a red tip.
  • Cartridge, Caliber .50, Incendiary, M1
This cartridge is used against unarmored, flammable targets. The incendiary bullet has a light blue tip.
  • Cartridge, Caliber .50, Ball, M2
This cartridge is used against personnel and unarmored targets. This bullet has an unpainted tip.
  • Cartridge, Caliber .50, Armor-Piercing, M2
This cartridge is used against lightly armored vehicles, protective shelters, and personnel, and can be identified by its black tip.
  • Cartridge, Caliber .50, Armor-Piercing-Incendiary, M8
This cartridge is used, in place of the armor piercing round, against armored, flammable targets. The bullet has a silver tip.
  • Cartridge, Caliber .50, Tracer, M10
Tracer for observing fire, signaling, target designation, and incendiary purposes. Designed to be less intense than the M1 tracer, the M10 has an orange tip.
  • Cartridge, Caliber .50, Tracer, M17
Tracer for observing fire, signaling, target designation, and incendiary purposes. Can be fired from the M82/M107 series of rifles.
  • Cartridge, Caliber .50, Armor-Piercing-Incendiary-Tracer, M20
This cartridge is used, in place of the armor piercing round, against armored, flammable targets, with a tracer element for observation purposes. This cartridge is effectively a variant of the M8 Armor-Piercing Incendiary with the added tracer element. Can be fired from the M82/M107 series of rifles. This bullet has a red tip with a ring of aluminum paint.
  • Cartridge, Caliber .50, Tracer, Headlight, M21
Tracer for use in observing fire during air-to-air combat. Designed to be more visible, the M21 is 3 times more brilliant than the M1 tracer.
  • Cartridge, Caliber .50, Incendiary, M23
This cartridge is used against unarmored, flammable targets. The tip of the bullet is painted blue with a light blue ring.
  • Cartridge, Caliber .50, Ball, M33
This cartridge is used against personnel and unarmored targets. Can be fired from the M82/M107 series of rifles.
  • Cartridge, Caliber .50, Saboted Light Armor Penetrator, M903
This is a Saboted Light Armor Penetrator (SLAP) round, which uses a smaller 355-360 grain bullet fitted in an amber colored plastic sabot. For use only in the M2 series of machine guns.
  • Cartridge, Caliber .50, Saboted Light Armor Penetrator-Tracer, M962
Like the M903, this is a Saboted Light Armor Penetrator (SLAP) round, with the only difference being that the M962 also has a tracer element for observing fire, target designation, and incendiary purposes. It uses red colored plastic sabot for indentification. For use only in the M2 series of machine guns.
  • Cartridge, Caliber .50, Ball, XM1022
A long-range match cartridge specifically designed for long range work using the M107 rifle.
  • Cartridge, Caliber .50, M1022 Long Range Sniper
The .50 Caliber M1022 has an olive green bullet coating with no tip ID coloration. The projectile is of standard ball design. It is designed for long-range sniper training and tactical use against targets that do not require armor piercing or incendiary effect. It exhibits superior long range accuracy and is trajectory matched to MK211 grade A. The M1022 is ideal for use in all .50 Caliber bolt action and semi-automatic sniper platforms.[3]
A so-called "combined effects" cartridge, the Mk 211 Mod 0 High-Explosive-Incendiary-Armor-Piercing (HEIAP) cartridge contains a .30 caliber tungsten penetrator, zirconium powder, and Composition A explosive. It can be used in any .50 caliber weapon in US inventory with the exception of the M85 machine gun. Cartridge is identified by a green tip with a grey ring.
  • Cartridge, Caliber .50, MK257 Armor Piercing Incendiary Dim Tracer
The .50 Caliber MK257 API-DT has a purple bullet tip. The bullet has a hardened steel core and incendiary tip. The .50 Caliber MK257 is used in machine guns M2, M3, and M85. Dim trace reduces the possibility of the weapon being located during night fire and is visible with night vision devices only.[3]
  • Cartridge, Caliber .50, Armor-Piercing-Incendiary-Tracer, Mk 300 Mod 0
As with the Mk 211 Mod 0, but with a tracer component. This cartridge likely can be used in any .50 caliber weapon in US inventory with the exception of the M85 machine gun, as with the Mk 211 Mod 0. Cartridge is identified by an unknown coloring.
  • Cartridge, Caliber .50, Armor-Piercing-Explosive-Incendiary, APEI-169, M02
This cartridge is used against hardened targets such as bunkers, for suppressive fire against lightly armored vehicles, and ground and aerial threat suppression. It is generally fired either from pilot-aimed aircraft-mounted guns or anti-aircraft platforms both produced by FN Herstal.[4] It is identified by a gray over yellow tip.[5] A tracer variant of it also exists.

The specified maximum diameter of an unfired .50 BMG bullet is 0.510-inch (13.0 mm); while this appears to be over the .50 inch (12.7 mm) maximum allowed for non-sporting Title I small arms under the U.S. National Firearms Act, the barrel of a .50 BMG rifle is only 0.50 inches (13 mm) across the rifling lands, and slightly larger in the grooves. The oversized bullet is formed to the bore size upon firing, forming a tight seal and engaging the rifling, a mechanism which in firearms terms is known as engraving. Subject to political controversy due to the great power of the cartridge (it is the most powerful commonly available cartridge not considered a destructive device under the National Firearms Act), it remains popular among long-range shooters for its accuracy and external ballistics. While the .50 BMG round is able to deliver accurate shot placement (if match grade ammunition is used) at ranges over 1,000-yard (910 m), smaller caliber rifles produce better scores and tighter groups in 1,000-yard (910 m) competitions.[6]

Since the adoption of .50 BMG rifles by military sniper units, there has been a growing gun control movement in some states, including California, New York, Massachusetts, Hawaii, and Illinois, to ban civilian possession of .50 BMG rifles and ammunition. Bill AB50 in California, passed in 2004, known as the .50 Caliber BMG Regulation Act of 2004 classifies all .50 BMG rifles of any action type as assault weapons, which are illegal to import into the state or transfer to any but a state agency or dealer licensed to purchase them. The bill's sponsor, California Assemblyman Paul Koretz, claimed that the .50 BMG "would be an ideal choice for use in an act of terrorism."

However, .50 BMG caliber rifles have lengths usually between four and five feet (1.2-1.5 meters) and weights from 20 to 40 pounds (10–20 kg), making the heaviest .50 caliber rifle similar in weight to an olympic sized barbell bar with no weights on it, sized similar to a pair of skis. This makes them unwieldy and difficult to conceal, and are a rarity in crime statistics. For example, the Violence Policy Center is only able to document 4 actual uses of .50 BMG rifles by criminals,[7] and only accounts for a total of 18 additional cases in which a .50 caliber rifle was recovered from the possession of a criminal without the gun having been used in a crime. The General Accounting Office prepared a report in 1999, in which it stated that the ATF had only received a total of 18 "traces" for 50 BMG rifles related to criminal activity for rifles made by the largest of 50 BMG manufacturers, Barrett.[8] Of these only one "trace" related to claimed actual use of a rifle, and deals with a highly controversial event itself, the Waco siege of the Branch Davidian ranch by the ATF and FBI.

After AB50 was passed, Barrett proceeded to cease sales and service of .50 BMG rifles to California law enforcement agencies. An official press release from the owner of Barrett Firearms can be found on the company's website, as follows: "The California legislature has banned the .50 BMG from the good citizens of the state of California, violating their rights and the constitution of our republic. Therefore, Barrett will not sell to or service any California government agencies."

In response to legal action against the .50 BMG in the United States and Europe, an alternative chambering was developed. The .510 DTC Europ uses the same bullet, but has slightly different case dimensions. .510 DTC cases can be made by fire-forming .50 BMG cases. The new round has almost identical ballistics, but because of the different dimensions, rifles chambered for .510 DTC cannot fire the .50 BMG, and therefore do not fall under many of the same legal prohibitions. Barrett offers a similar alternative, the .416 Barrett, which is based on a shortened .50 BMG case necked down to .416 caliber (10.3 mm).

Despite the otherwise strict firearms laws within the United Kingdom it is possible to own a .50 BMG rifle as a section 1 firearm.

Typical uses

The primary military use of this round is in the Browning M2HB heavy machine gun.

The primary civilian users of .50 caliber rifles, which range in price from around USD$1,600[9] for single shot AR-15 upper conversions to well over USD$8,000[10] for the semi-automatic, magazine-fed Barrett M82A1, are long-range target shooters; the Fifty Caliber Shooters Association, for instance, holds .50 BMG shooting matches nationwide in the U.S.[11]

The U.S. Coast Guard uses .50 BMG weapons for drug interdictions. Effective interdiction requires that personnel on Coast Guard cutters be able to deliver accurate fire to stop high-speed drug runners. Similarly, .50 BMG weapons have attracted attention from law enforcement agencies; they have been adopted by the New York City Police Department. If it becomes necessary to immobilize a vehicle, a .50 BMG round in the engine block will shut it down quickly. If it is necessary to breach barriers, a .50 BMG round will penetrate most commercial brick walls and concrete cinder blocks.

In addition to long-range and anti-materiel sniping, the U.S. military uses .50 BMG weapons to detonate unexploded ordnance from a safe distance. The Raufoss Multipurpose round has sufficient terminal performance to disable most unarmored and lightly armored vehicles, making .50 BMG caliber weapons helpful in anti-insurgency operations.

The cartridge is also used by some hunters for taking game at extreme ranges; while the energy of the .50 BMG at close range is excessive for most game, at long ranges the velocity has dropped to levels that allow the taking of game animals without excessive damage to the animal.[12][13]

Partial list of .50 BMG firearms

Carbine rifles:

  • Barrett M82CQ (a carbine version of the M82A3)

Rifles:

Machine guns

See also

References

  1. ^ Friscolanti, Michael (5/15/2006). "We were abandoned", Macleans 119 (20).
  2. ^ http://www.dtic.mil/dticasd/sbir/sbir032/a044a.pdf
  3. ^ a b http://www.atk.com/ammo_PDFs/smallcaliber.pdf
  4. ^ Janes listing of the FN Herstal .50 cal M3P coaxial weapon system (Belgium).
  5. ^ Igman Ammunition Cal. 12.7 x 99 mm, APEI, M 02.
  6. ^ GunWeek.com. "SHOT Show 2006 New Rifles, Shotguns, Pistols Offer Enhanced Performance".
  7. ^ VPC inaccurately titled page VPC Criminal Use of the 50 Caliber Sniper Rifle
  8. ^ Briefing Paper: Criminal Activity Associated with .50 Caliber Semiautomatic Rifles
  9. ^ Ultralite 50
  10. ^ "The Model 82A1/M107 from Barrett Firearms". Archived from the original on 2009-08-10. Retrieved 2009-08-08. {{cite web}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  11. ^ Match dates at the Fifty Caliber Shooters Association
  12. ^ Daniel Lilja. "Chuck Hunting with the 50 BMG".
  13. ^ "Way Out There: Shooting (And Hunting With) The .50 Caliber Browning Machine Gun Cartridge". Field and Stream.
  14. ^ http://www.amsd.ch
  15. ^ http://www.pindad.com
  16. ^ http://www.bluegrassarmory.com
  17. ^ http://www.statearms.com
  18. ^ http://www.bushmaster.com
  19. ^ http://www.halo-arms.com
  20. ^ POLY-Technologies M99 anti-matériel rifle series on Modern Firearms.net
  21. ^ POLY-Technologies M99b anti-matériel rifle series on Modern Firearms.net
  22. ^ http://www.securityarms.com/20010315/galleryfiles/2500/2540.htm
  23. ^ http://www.safetyharborfirearms.com
  24. ^ "only long range". Archived from the original on 2009-04-19. Retrieved 2009-03-24.
  25. ^ http://www.Ultralite50.com
  26. ^ http://www.vulcanarmament.com
  27. ^ http://02bfe1c.netsolhost.com/products/m96.htm
  • TM43-0001-27 US Army Ammunition Data Sheets - Small Caliber Ammunition, HQ Department of the Army, 6/81, Including changes (Not to be used as reloading data)
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