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24 year-old Forester Rocky Baucum from Alma, has interests which includes metal detecting, [http://ganhedinheironainternet.comoganhardinheiro101.com como ganhar dinheiro] na internet and cooking. Likes to visit unknown cities and spots like Imperial Palaces of the Ming and Qing Dynasties.
[[Image:Airsoft pellets.jpg|thumb|right|150px|Low quality 6 mm 0.12 g plastic airsoft pellets]]
{{Refimprove|date=July 2013}}
'''Airsoft pellets''' are [[spherical]] [[projectiles]] used in [[Airsoft gun]] models. Typically made of [[plastic]],<ref name="Habibu">{{Cite news |url=http://thestar.com.my/news/story.asp?file=/2013/6/19/nation/13258814&sec=nation |title=Airsoft guns are easily available online |date=19 June 2013 |last=Sira |first=Habibu |publisher=The Star Online |accessdate=29 June 2013}}</ref><ref>{{Cite news |url=http://www.cbs12.com/news/top-stories/stories/vid_8362.shtml |title=Woman Uses Airsoft Toy Gun To Scare Off Intruder In Deerfield Beach Apartment |date=27 June 2013 |authors=Brett Clarkson, Erika Pesantes and Robert Nolin |accessdate=29 June 2013}}</ref> they usually measure around 6&nbsp;mm<ref>{{Cite web |url=http://www.airsoftatlanta.com/What-is-Electric-Rifle-Gun-s/416.htm |title=What is an electric rifle?  AEG Airsoft guns explained |accessdate=27 June 2013}}</ref> in diameter, though select models use 8mm, and weigh between 0.12 and 0.48 g, with the most popular weights being 0.12g and 0.20g. Although sometimes called '''BBs''', they are not the same as the 4.5&nbsp;mm projectiles fired by [[BB guns]].
 
== Variants ==
 
Although the majority of pellets bought and used are simple spherical projectiles made of plastic, some of the following special varieties can be used to give a player an advantage.
 
===Biodegradable===
[[Biodegradable]] pellets are available, and are often required by outdoor fields where sweeping up is not an option. Conventional pellets pollute the environment, as most non-biodegradable pellets have a mineral- or petroleum-based center, coated in non-biodegradable plastics, thus ensuring they will stay in the environment for several hundred years if not collected. Biodegradable pellets are made of various types of resin, often developed for the agricultural industry, and better makes are certified as compostable.
 
There is a mixture of degradable processes being used, such as soil microbes and photosensitive degradation. Biodegradable pellets are currently being produced with all the characteristics of the best of the conventional, with homogeneous resin construction.
 
Bio pellets struggle to remain true to the name when approaching weights equal or greater than 0.30g and more research is needed on production materials.
 
===Tracers===
[[Phosphorescence|Glow-in-the-dark]] pellets, known as ''[[Tracer ammunition|tracer]]'' pellets, can be used in conjunction with a device that "charges" the pellets by flashing them with a burst of light before leaving the barrel, so that they remain [[luminescent]] in flight for use during nocturnal games/operations. This tracer unit is usually hidden from view, often disguised as a [[suppressor]] (silencer), or is included inside the magazine or [[Hop-Up (Airsoft)|hop-up unit]]. There are also biodegradable glow-in-the-dark pellets available.
 
===Paintball Pellets===
[[Paint]]-filled pellets are also available, called paintballs, which are very similar to those used in [[paintball]].  Airsoft models equipped with the hop-up projectile stabilizing system are not able to use these, as the thin shells are liable to break in the barrel, soiling it with paint.  These special pellets are also incompatible with Airsoft models using mechanized feed systems, such as high capacity magazines, for the same reason. With some companies, the use of paintballs voids the airsoft gun's warranty; paint may get into the mechanical workings of the airsoft gun and damage parts beyond simple maintenance. These issues may be fixed by removing the hop-up unit, which can void the warranty, and also switching to a low or mid-capacity magazine with no mechanized feed.
 
===Markers===
Recently, a new kind of pellet that leaves a small mark has emerged on the market. The pellets are coated with a powder that, when it strikes the target, a mark is left. Manufacturers include Verdict and Grudge Tactical. However, these suffer from similar issues to the above — the powder often jams up guns, magazines, barrels or hop up units. While initially considered "safer", these have proven to be little better than paintball pellets. Actually there are other types of markers too. The first ones came out in 2008 and were manufactured for D/TS Products Group based on their specifications.though these were designed to be used in AEG guns exclusively they are now being marketed by realizing paintball as working in all guns. That is were the problem lies the shell is a softgel encapsulation that is highly susceptible to moisture and will swell when in 60% humidity or higher. Also in temperatures below 50° or higher than 90° shell softened causing problems. The softened shell will allow the deformation of the marker in the magazine causing jams and breakage. There'll be a new product introduced in 2014, by D/TS Products Group. This new round is a heavyweight marker( .23 g) with a waterproof shell that will allow marking at greater distances reliably.
 
===Silica or Bio-Inert===
Made from 100% silica, these BBs (most notably from BIOval and BB Bastard) have the advantage of very even material distribution and hence great flight characteristics. However, there are scattered accounts of these breaking glass and even defeating ANSI 87.1Z rated (standard) protective eye-wear. The community is currently undecided on this issue. These BBs are prohibited by most airsoft grounds due to a number of major injuries.
 
===Metallic===
Specially designed and built metallic 6&nbsp;mm BBs for airsoft guns can be found on the market. These metallic BBs should typically not be used for airsoft play because they can break airsoft players' eye protection at close range, and cause fatal injuries{{Citation needed|date=October 2013}}. These are typically designed for very high velocity sniper rifles and should only be used for target shooting due to increased safety concerns. These airsoft pellets are heavy which means they lower the fps (feet per second) but they increase the amount of damage on an object{{Citation needed|date=October 2013}}.
 
===Ceramic===
Created from lab grown crystal lattice structures, these BBs are individually CNC machined. The result is a BB that contains no voids, is perfectly spherical and is exactly the same weight from BB to BB. The downside is they are extremely expensive. Like metallic BBs, they can defeat standard eye protection at close ranges and should only be used for long distance.
 
==Pellet mass==
 
Pellet mass is an important factor when choosing pellets. The pellet's mass influences several aspects of pellet performance:
 
'''Velocity:'''
*Lighter pellets achieve higher velocities, but are more prone to influence from external factors like wind. Lighter pellets also decelerate (lose velocity) faster than heavier pellets.  Due to the increased momentum of a heavier pellet, it will hit harder than a lighter one. In addition, while apparently counter intuitive, lighter pellets can actually decrease range due to the mechanics of hop up.
'''Trajectory:'''
*The curvature of a projectile (trajectory) determines its range and lighter pellets typically result in much more curved or unpredictable trajectories. [[Hop-Up (Airsoft)|hop-up]] can flatten, regulate and extend trajectory.
'''Hardware:'''
*Heavier pellets may require a more powerful [[airsoft gun]] and often necessitates upgraded springs and other gun parts.
 
A player's choice of pellet mass is governed by their gaming style, airsoft gun (internals), game location (in/outdoor), high/low range and feet-per-second regulations.
 
Also, quality of the individual BBs may influence choice of price-range or manufacturer. Low-cost BBs are often considered to have such negative characteristics as residual plastic from the moulding process ([[Flash (manufacturing)|flash]]); lower impact resistance and some deviation from perfect spherical shape. Cheaper BBs are known to shatter when fired, which can cause irreparable damage to the internals of the gun. Higher cost BBs generally have a smoother finish, are more impact resistant and are perfectly spherical.
 
===6 mm Airsoft pellet mass and their usage===
*0.11 g - Manufactured by HFC, same use as .12&nbsp;gram. Extremely Uncommon.
*0.12 g - Extremely common, standard weight for all low grade AEG's and spring guns. Not to be used in any small arms beyond low-cost, low quality replicas firing under 250fps.
*0.135 g - Same uses as 0.12 g. Extremely Uncommon. MFI standard. Not to be used in most guns.
*0.15 g - Same uses as 0.12 g. Uncommon. made by only [[Air Venturi]]
*0.16 g - Essentially the same as the 0.15 g pellets. made only by [[Air Venturi]]
*0.20 g - Second most common weight. Standard for almost all velocity tests. AEGs are able to use these, however, most experienced players will use heavier masses due to the increased accuracy and range. Bio versions made by Green Devil being one of the most popular makes in the Scandinavian countries and many other parts of Europe, & UK.
*0.22 g - no longer in production. Used to be available from KWC and Western Arms.{{Citation needed|date=November 2010}}
*0.23 g - Heavier pellets for AEGs. Blends speed of 0.20 g with range and accuracy of 0.25 g. Made popular by [[Tsunami Airsoft]]. Used less now in favor of .20g & .25g
*0.24 g - Only known manufacturers are Airstrike (a subsidiary of [[Daisy Outdoor Products|Daisy]]) and [[Crosman]]
*0.25 g - Heaviest mass for lower powered AEGs, blowback and spring guns. [[Tokyo Marui]] standard AEG, gas, and spring guns are set at the factory for 0.25&nbsp;gram BBs, and they usually include a package of 200 of these with the gun. Bio versions made by Green Devil being one of the most popular makes in the Scandinavian countries and many other parts of Europe, & UK.
*0.26 g - Made by TSD in biodegradable form.
*0.27 g - Made by Bioval BBBMAX. They are (ostensibly) considered to be of the same grade, if not higher than the Maruzen SGM, while being significantly less expensive.
*0.28 g - For higher velocity AEGs or sniper rifles. Typically cheaper than 0.30 g but yields similar performance. Bio versions are made by Green Devil, one of the most popular manufacturers in Europe.
*0.29 g - Maruzen Super Grandmaster BBs, designed for their Air Precision Shooting series of guns. One of the most precisely ground and accurate BBs available{{Verify source|date=July 2007}}, but cost roughly 10x more than typical alternatives.
*0.30 g - Standard mass for most [[sniper rifles]]. Have become more common in recent times with some of the top brands like Bioval and Bioshot, Bio versions made by Green Devil being one of the most popular makes in the Scandinavian countries and many other parts of Europe, & UK.
*0.32 g - Also standard for sniper rifles. Offers excellent balance of velocity and stability for most spring and gas sniper rifles. A well-known brand is Goldenball.
*0.36 g - Heavier pellets for [[sniper rifles]]. Slower, but have high stability. Produced by Madbull Airsoft, among others. BB Bastard manufactures a ceramic BB in this mass class.
*0.40 g - Heavy pellets for airsoft sniper rifles. Mad Bull is a known producer. Even slower than 0.36g but even more stable and maintains its velocity better.
*0.43 g - For the highest level of upgrades in spring and gas [[sniper rifles]]. Usually [[graphite]] coated.
*0.66 g - For extreme long range, not used against human targets. This is a ceramic CNC machined BB made by BB Bastard.
*0.90 g - Nickel-plated steel BBs sold by Abacus Claysports of the UK.
 
===8 mm Airsoft pellet masses===
*0.27 g - Low mass
*0.34 g (Normal)- Standard mass
*0.35 g (Biodegradable)- Standard mass
*0.4  g
*0.45 g
*0.48 g
*0.50 g
*0.90 g Heaviest mass
 
== Pellet ballistics ==
 
=== Pellet muzzle velocity and energy ===
The pellet speed of automatic electric guns is determined in large part by the tension of the main spring of the gun.
Airsoft muzzle (at gun's exit) speed limits are between {{convert|300|and|400|ft/s|m/s|abbr=on}} for AEGs and {{convert|400|to-|550|ft/s|m/s|abbr=on}} for single shot guns ([[sniper rifles]]).{{citation needed|date=December 2012}}
 
[[Image:Fps vs joules.jpg|thumb|Velocity vs. energy chart for 6 mm Airsoft pellets.]]
 
For comparison purposes, 3.00g is the typical mass of a [[paintball]] pellet and 0.2g is the standard for an airsoft pellet.
At 3g mass, a pellet flying at {{convert|100|m/s}} results in 15J of kinetic energy, while a 0.2g results in 1J.
It is important to distinguish that, on airsoft, the impact energy is very close to the kinetic energy of the pellet because the collision is almost [[elastic collision|elastic]].
On the other hand, in paintball, the pellet disintegrates on the collision, leading to an [[inelastic collision]] and thus the impact energy is smaller than the kinectic energy of the pellet.
Nevertheless, the typical impact energies of the airsoft pellet tend to be much smaller than of the paintball.
 
=== Pellet ballistics ===
 
While the pellet's velocity leaving the airsoft gun is important for safety proposes, during flight, it loses velocity due to drag. The typical deceleration of a pellet of mass "m" and diameter "D" is given by the [[Drag_(physics)#Drag_at_high_velocity|quadratic drag]]:
 
[[File:Impact energy dependence on distance on airsoft.pdf|thumb|impact energy dependence on distance of impact for a typical airsoft pellet]]
 
:<math> A_{drag} = \frac{1}{2m}\rho_{air}v^2 \cdot 0.47 \cdot \pi \left(\frac{D}{2}\right)^2</math>
 
where v is the instantaneous velocity of the pellet. For typical values of the pellet (m = 0.2 g, v = 120&nbsp;m/s, D = 0.6&nbsp;mm), the drag can be very high (<math>576 m/s^2</math>) which means that the velocity decreases quite fast. In particular, for typical values and neglecting wind effects and hop-up techniques, a straight shot from a height of 1.8m has a range of 34m. On ground hit, the impact energy of the pellet is 0.1 J. However, the same shot at close quarters (e.g. 5m distance) has an impact energy of 1J (see figure).
 
=== Dangers to humans ===
{{see also|Airsoft#Safety}}
Airsoft pellets typically leave small [[Cutaneous_conditions#Primary_lesions|lesions]] (welts) on exposed skin with human targets. While mildly painful, pellets are not typically damaging to the skin. Eye protection is universally mandatory to prevent damage to eyes. It is also often recommended that full face masks and body protection be used during airsoft matches to protect the players' teeth and ears.
 
Experiments on bullets allow to estimate the minimum velocity for an airsoft pellet to penetrate in skin (where penetration means that the spherical pellet enters more than half in the skin). In 1978, it was measured<ref name=Tausch/> that the critical velocity to skin penetration can empirically be given by:
 
:<math>v_{cr} = 162.1 e^{-0.38 \sqrt{m}}</math>
 
where m is the mass of a spherical bullet, in grams. This means that a typical 0.2g airsoft pellet will penetrate skin at {{convert|136.7|m/s}}, or 1.87J.
 
The following excerpts are from the United Kingdom Parliament's "Principles of firearms control",
Home Affairs Select Committee Second Report, 6 April 2000, expound on the level of danger involved with low-energy projectiles:
 
<blockquote>
"25. The Firearms Act 1968 defines a firearm "a lethal barreled weapon of any description from which any shot, bullet or other :missile can be discharged".[51] In this context, a "lethal weapon" means a weapon capable of firing a projectile with sufficient :force to inflict more than a trivial injury, i.e. with a force sufficient to puncture the skin.[52] The force with which a firearm :is able to deliver a projectile is normally expressed in terms of the kinetic energy it generates at its muzzle—the "muzzle energy". :This energy is normally expressed in units of foot-pounds (ft·lbs) or joules (J).[53]
 
"26. The Home Office and the Forensic Science Service considers that the lowest level of muzzle energy capable of inflicting a penetrating wound is one foot pound force (1.35 J): below these power levels, weapons are "incapable of penetrating even vulnerable parts of the body, such as the eye".[54] However, more recent analysis by the Forensic Science Agency for Northern Ireland has indicated that a more reasonable assessment of the minimum muzzle energy required to inflict a penetrating wound lies between 2.2 and 3.0 ft·lbf (3 to 4 J).[55] We will deal more fully with this discrepancy at paragraphs 123 to 130 below."
 
"123. The power level at and above which an air weapon is considered a firearm in law is presently set at 1 ft·lbf. However, the Forensic Science Agency of Northern Ireland has more recently assessed the power level at which a barreled weapon is capable of inflicting a lethal wound as between 2.2 and 3 ft·lbf, and the Secretary of State for Northern Ireland has proposed that the law relating to firearms in Northern Ireland be amended to take this into account.[201]"
</blockquote>
 
On another document also regarding firearms, "The Eleventh Annual Report of the Firearms Consultative Committee", the penetration levels lies between 2 and 3 J based on a research for US Army and DiMaio's work in "Minimal Velocities Necessary for Perforation of Skin by Air Pellets and Bullets, Journal of Forensic Sciences".
 
{|cellpadding="0" cellspacing="7" style="margin: 1em 1em 1em 1em; border:3px solid #cccccc;" align="center"
|- bgcolor="#cccccc"
| Date || Reference || Energy level || Observations ||
|-
| April 2000 || Principles of firearms control [paragraph 26],Home Office and the Forensic Science Service; || 1,35J || penetrating wound (later changed by paragraph 123, see below)||
|-
| April 2000 || Principles of firearms control [paragraph 123], Forensic Science Agency for Northern Ireland; || 3,00J~4,00J|| penetrating[26]/lethal[123] wound ||
|-
| March 2002 || The Eleventh Annual Report of the Firearms Consultative Committee DiMaio's work in Minimal Velocities Necessary for Perforation of Skin by Air Pellets and Bullets, Journal of Forensic Sciences;|| 2,00J~3,00J|| penetration level ||
|}
 
==References==
{{reflist|
refs=
<ref name=Tausch>{{cite doi| 10.1007/BF02096436
}}</ref>
}}
 
==See also==
*[[BB gun]]
*[[Pellet (air gun)]]
 
{{DEFAULTSORT:Airsoft Pellets}}
[[Category:Airsoft]]
[[Category:Pneumatic weapons]]

Latest revision as of 09:07, 29 October 2014

24 year-old Forester Rocky Baucum from Alma, has interests which includes metal detecting, como ganhar dinheiro na internet and cooking. Likes to visit unknown cities and spots like Imperial Palaces of the Ming and Qing Dynasties.