Green bullet, green ammunition or green ammo are nicknames for a United States Department of Defense program to eliminate the use of hazardous materials from small arms ammunition and from small arms ammunition manufacturing. Initial objectives were elimination of ozone-depleting substances, volatile organic compounds, and heavy metals from primers and projectiles. These materials were perceived as causing difficulties through the entire life cycle of ammunition. The materials generated hazardous wastes and emissions at manufacturing facilities and use of ammunition caused contamination at shooting ranges. Potential health hazards made demilitarization and disposal of unused ammunition difficult and expensive. [2]
The Joint Working Group for Non-Toxic Ammunition was formed by the Small Caliber Ammunition Branch of the United States Army Armament Research, Development and Engineering Center in October 1995. Members of the working group included the National Guard of the United States, the United States Coast Guard, the United States Army Infantry School, the Industrial Operations Command, the Lake City Army Ammunition Plant, the Oak Ridge National Laboratory, the Los Alamos National Laboratory and the United States Department of Energy Kansas City Plant. [2]
In 2013, lead bullet production represented the second largest use of lead in the U.S., after lead-acid batteries. [3] Studies by the U.S. CDC suggest blood lead levels are correlated with self-reported consumption of game meat. [4]
October 11, 2013 Governor Jerry Brown of California signed into law AB 711 Hunting: nonlead ammunition. [5] Cost reductions from conversion to green ammo are estimated at "$2.5 million required for waste removal at each outdoor firing range as well as the $100 thousand annual costs for lead contamination monitoring". [6]
Hazardous material | Location [2] | New material |
---|---|---|
antimony | projectile | tungsten-tin or -nylon [7] |
antimony trisulfide | primer | diazodinitrophenol (DDNP) [8] |
barium nitrate | tracer or incendiary projectile | |
barium peroxide | primer and tracer or incendiary projectile | diazodinitrophenol |
ethyl acetate | blank cartridge tip sealant | Solventless process [9] |
ethyl alcohol | tracer or incendiary projectile | |
glycol ether | painted projectile point | |
lead | projectile | steel [10] tungsten-tin or tungsten-nylon [11] [12] [13] copper [14] |
lead dioxide | tracer or incendiary projectile | |
lead styphnate | primer | diazodinitrophenol, MIC, e.g. Al/MoO3 |
methyl chloroform | casemouth sealant and tracer or incendiary projectile | |
methyl ethyl ketone | primer and sealants for primer pocket and blank cartridge tip | Solventless process |
methyl isopropyl ketone | primer and sealants for primer pocket and blank cartridge tip | Solventless process |
toluene | primer and sealants for primer pocket and blank cartridge tip | Solventless process |
xylene | sealants for primer pocket and blank cartridge tip |
Two green ammunition cartridges are the 5.56×45mm NATO M855A1 and the MK281 40 mm grenade. Switching to the 5.56 mm green bullet, the M855A1 Enhanced Performance Round, or EPR, in 2010 has eliminated nearly 2,000 tons of lead from the waste stream. [15] U.S. Army representatives at a 2013 House Armed Services Committee hearing have credited the 5.56mm M855A1 Enhanced Performance Round “close to” those of a 7.62mm in its performance capabilities. [16] The longer, less dense M855A1 bullet must be seated deeper than the lead core bullet it replaced to maintain the same exterior cartridge dimensions required for reliable functioning in self-loading firearms; and higher pressure is required to obtain the same bullet velocity with reduced propellant volume. Increased pressure causes gas port erosion producing a higher cyclic rate of automatic fire making jamming malfunctions more likely. Cracks in bolt locking lugs have been observed after 3000 rounds of full automatic fire with the M855A1 cartridge. [17]
Enhanced Performance Round, Lead-Free
The Army Research Laboratory and other participants developed the M855A1, Enhanced Performance Round (EPR), by applying ballistics concepts originally used in large-caliber cartridges to small arms. The result was significant improvements to lethality of small arms. [18] [19] The 5.56-mm (M855A1) ammunition was first battle-tested in mid-2010 in Afghanistan. The 7.62-mm (M80A1) ammunition was fielded in 2014. [18]
The EPR “bronze tip” ammo – previously known generically as “Green Ammo” – was born at the kickoff meeting for Phase II of the Army's Green Ammunition replacement program in mid-2005, at the Lake City Army Ammunition Plant. Participants met to discuss problems surrounding environmentally-friendly small arms training ammunition. [18]
The program team was composed of Project Manager, Maneuver Ammunition Systems (PM-MAS), Army Research Laboratory (ARL), U.S. Army Armaments Research Development and Engineering Center (ARDEC), and other team members. Participants evaluated more than 20 potential projectile designs before moving forward with a three-piece, reverse-jacket bullet design incorporating a hardened steel penetrator and lead-free slug. [20]
The EPR produces consistent effects against soft targets; increased effectiveness at long ranges; increased defeat of hard targets; and reduced muzzle flash (to help conceal soldiers’ firing positions). The lead-free cartridges also reduce environmental impact by removing more than 2,000 metric tons of lead per year that otherwise could end up in the environment. [18] [19]
The EPR contains an environmentally-friendly projectile that eliminates lead from the manufacturing process in direct support of Army commitment to environmental stewardship. [21] Under the Green Ammo Phase II initiative, the Army focused on lead-free ammo in stateside training ranges, in response to tightening state environmental regulations. [18]
Some of a bullet's kinetic energy is typically converted to heat if the bullet strikes a hard surface like rock. Collision debris may include high temperature bullet fragments as sparks. Steel core and solid copper ammunition have the highest potential to start wildfires. Lead core bullets are less likely to ignite surrounding vegetation. [22] [23]
Rifling is required to stabilize elongated bullets, and longer bullets require faster rotation for similar stability. The rate of rotation is determined by the twist of the lands and grooves engraved on the interior of a rifled barrel. Twist is usually expressed as the length of barrel (in inches) in which the bullet will rotate through a full 360 degrees; so bullets fired from a 1:10" twist rifle will make a complete rotation in every 10 inches (25 cm) of distance traveled. [24]
Since lead is a very dense material, bullets made of inexpensive, non-toxic materials will be lighter than bullets made of lead unless bullet length is increased. Inferior external ballistics cause lighter bullets to be less effective against distant targets. Increasing bullet length may require a faster rifling twist to maintain stability. Some early trials versions of the M16 rifle had 1:14" twist barrels, but this was increased to 1:12" twist in early military production to improve stability with 55-grain (3.6 g) M193 lead-core bullets in the early 5.56×45mm NATO cartridges. Twist was increased to 1:9" after combat experience demonstrated the advantages of longer 62-grain (4.0 g) M855 bullets with a portion of the lead core replaced by a less dense steel penetrator. Barrels with 1:7" twist have been used in 21st century 5.56×45mm NATO firearms and have replaced barrels of older United States military firearms to stabilize longer M856 tracer bullets and M855A1 green bullets of less dense materials. [25]
The 5.56×45mm NATO is a rimless bottlenecked intermediate cartridge family developed in the late 1970s in Belgium by FN Herstal. It consists of the SS109, L110, and SS111 cartridges. On 28 October 1980, under STANAG 4172, it was standardized as the second standard service rifle cartridge for NATO forces as well as many non-NATO countries. Though they are not identical, the 5.56×45mm NATO cartridge family was derived from and is dimensionally similar to the .223 Remington cartridge designed by Remington Arms in the early 1960s.
A bullet is a kinetic projectile, a component of firearm ammunition that is shot from a gun barrel. They are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax; and are made in various shapes and constructions, including specialized functions such as hunting, target shooting, training, and combat. Bullets are often tapered, making them more aerodynamic. Bullet size is expressed by weight and diameter in both imperial and metric measurement systems. Bullets do not normally contain explosives but strike or damage the intended target by transferring kinetic energy upon impact and penetration.
A cartridge, also known as a round, is a type of pre-assembled firearm ammunition packaging a projectile, a propellant substance and an ignition device (primer) within a metallic, paper, or plastic case that is precisely made to fit within the barrel chamber of a breechloading gun, for convenient transportation and handling during shooting. Although in popular usage the term "bullet" is often used to refer to a complete cartridge, the correct usage only refers to the projectile.
The .40 S&W (10.2×22mm) is a rimless pistol cartridge developed jointly by American firearms manufacturers Smith & Wesson and Winchester in 1990. The .40 S&W was developed as a law enforcement cartridge designed to duplicate performance of the Federal Bureau of Investigation's (FBI) reduced-velocity 10mm Auto cartridge which could be retrofitted into medium-frame semi-automatic handguns. It uses 0.40-inch-diameter (10 mm) bullets ranging in weight from 105 to 200 grains.
The .380 ACP, is a rimless, straight-walled pistol cartridge developed by firearms designer John Moses Browning. The cartridge headspaces on the mouth of the case. It was introduced in 1908 by Colt, for use in its new Colt Model 1903 Pocket Hammerless semi-automatic, and has been a popular self-defense cartridge ever since, seeing wide use in numerous handguns. Other names for .380 ACP include .380 Auto, 9×17mm, 9mm Browning, 9mm Corto, 9mm Kurz, 9mm Short, and 9mm Browning Court. It should not be confused with .38 ACP. The .380 ACP does not strictly conform to cartridge naming conventions, named after the diameter of the bullet, as the actual bullet diameter of the .380 ACP is .355 inches.
The 9×19mm Parabellum is a rimless, centerfire, tapered firearms cartridge.
The .22 Long Rifle, also known as the .22LR or 5.6×15mmR, is a long-established variety of .22 caliber rimfire ammunition originating from the United States. It is used in a wide range of firearms including rifles, pistols, revolvers, and submachine guns.
The .223 Remington is a rimless, bottlenecked, centerfire intermediate cartridge. It was developed in 1957 by Remington Arms and Fairchild Industries for the U.S. Continental Army Command of the United States Army as part of a project to create a small-caliber, high-velocity firearm. The .223 Remington is considered one of the most popular common-use cartridges and is currently used by a wide range of semi-automatic and manual-action rifles.
The .30-06 Springfield cartridge, 7.62×63mm in metric notation, and called the .30 Gov't '06 by Winchester, was introduced to the United States Army in 1906 and later standardized; it remained in military use until the late 1970s. In the cartridge's name, ".30" refers to the nominal caliber of the bullet in inches; "06" refers to the year the cartridge was adopted, 1906. It replaced the .30-03 Springfield, 6mm Lee Navy, and .30-40 Krag cartridges. The .30-06 remained the U.S. Army's primary rifle and machine gun cartridge for nearly 50 years before being replaced by the 7.62×51mm NATO and 5.56×45mm NATO, both of which remain in current U.S. and NATO service. The cartridge remains a very popular sporting round, with ammunition produced by all major manufacturers.
The .22 Long is a variety of .22 caliber (5.6 mm) rimfire ammunition. The .22 Long is the second-oldest of the surviving rimfire cartridges, dating back to 1871, when it was loaded with a 29 gr (1.9 g) bullet and 5 gr (0.32 g) of black powder, 25% more than the .22 Short on which it was based. It was designed for use in revolvers, but was soon chambered in rifles as well, in which it gained a reputation as a small game cartridge.
The .243 Winchester (6×52mm) is a popular sporting rifle cartridge. Developed as a versatile short action cartridge to hunt both medium game and small game alike, it "took whitetail hunting by storm" when introduced in 1955, and remains one of the most popular whitetail deer cartridges. It is also commonly used for harvesting blacktail deer, pronghorns and mule deer with heavier rounds, and is equally suited to varmint hunting with lighter rounds. The .243 is based on a necked down .308 Winchester, introduced only three years earlier. Expanding monolithic copper bullets of approximately 80 to 85 grains or traditional lead rounds of 90 to 105 grains with controlled expansion designs are best suited for hunting medium game, while lighter rounds are intended for varmints.
The 6.8mm Remington Special Purpose Cartridge is a rimless bottlenecked intermediate rifle cartridge that was developed by Remington Arms in collaboration with members of the U.S. Army Marksmanship Unit and United States Special Operations Command to possibly replace the 5.56 NATO cartridge in short barreled rifles (SBR) and carbines. Based on the .30 Remington cartridge, it is midway between the 5.56×45mm NATO and 7.62×51mm NATO in bore diameter. It uses the same diameter bullet as the .270 Winchester hunting cartridge.
Armor-piercing bullets for rifle and handgun cartridges are designed to penetrate ballistic armor and protective shields intended to stop or deflect conventional bullets. Although bullet design is an important factor with regard to armor penetration, the ability of any given projectile to penetrate ballistic armor increases with increasing velocity. Rifle cartridges typically discharge bullets at higher muzzle velocity than handgun cartridges due to larger propellant charge. However, even the same cartridge fired from a rifle will, in almost all common cases, have a higher velocity than when fired from a handgun. This is due to the longer period of acceleration available within the longer gun barrel of rifles, which allow adequate time for the propellant to fully ignite before the projectile exits the barrel. For this reason, bullets fired from rifles may be more capable of piercing armor than similar or identical bullets fired from handguns. In addition, a small-caliber bullet has higher sectional density than a larger-caliber bullet of the same weight, and thus is more capable of defeating body armor.
The two most common assault rifles in the world are the Soviet AK-47 and the American M16. These Cold War-era rifles have been used in conflicts both large and small since the 1960s. They are used by military, police, security forces, revolutionaries, terrorists, criminals, and civilians alike and will most likely continue to be used for decades to come. As a result, they have been the subject of countless comparisons and endless debate.
The .38 ACP, also known as the .38 Auto, .38 Automatic, or 9×23mmSR, is a semi-rimmed pistol cartridge that was introduced at the turn of the 20th century for the John Browning-designed Colt M1900. It was first used in Colt's Model 1897 prototype, which he did not produce. The metric designation for the round is 9×23mm SR (semi-rimmed), which is not to be confused with other 9×23mm cartridges.
The 5.8×42mm / DBP87 is a military bottlenecked intermediate cartridge developed in the People's Republic of China. There is limited information on this cartridge, although the People's Liberation Army claims that it is superior to the 5.56×45mm NATO and Soviet 5.45×39mm cartridges.
The following are terms related to firearms and ammunition topics.
The .300 AAC Blackout, also known as 7.62×35mm, is an intermediate cartridge developed in the United States by Advanced Armament Corporation (AAC) for use in the M4 carbine. The cartridge yields increased performance in shorter barrels and effective subsonic performance for silencer use when compared to 5.56mm NATO. The .300 AAC Blackout uses standard 5.56mm NATO magazines and components with the exception of the barrel.
The 7.62×51mm NATO is a rimless, straight walled, bottlenecked rifle cartridge. It is a standard for small arms among NATO countries.
The .277 Wolverine (6.8x39mm) is a wildcat cartridge. It is a multi-purpose mid-power cartridge with increased ballistic performance over the AR-15's traditional .223 Remington cartridge. The use of a modified 5.56 case means that at minimum, only a new barrel is needed to convert any 5.56-based firearm to .277 Wolverine.