Paintball equipment is central to paintball, given its equipment-intensive nature. Although good equipment by no means guarantees a good player, a good player's ability can be seriously hampered by poor-quality equipment. In order to safely conduct a game of paintball, every player requires, at a minimum, a marker with propellant to fire the paint, a mask to protect the eyes and face, paintballs, and a loader to hold them. To ensure safety off the playing field, a barrel sock or plug is also considered compulsory.
Common additional equipment, depending on type of play, often includes gloves, a pack designed to comfortably carry pods containing extra paintballs, and a squeegee or swab for cleaning out the barrel in case a paintball breaks.
Markers
Main article: Paintball markerA paintball marker is the primary piece of equipment used in paintball to tag an opposing player. An expanding gas (usually carbon dioxide or high-pressure air) forces a paintball through the barrel at a muzzle velocity of approximately 300ft/s (90m/s). This velocity is sufficient for most paintballs to break upon impact at a distance, but not so fast as to cause tissue damage beyond mild bruising. Nearly every commercial field has, and strictly enforces, a rule limiting the muzzle velocity of a paintball at or below 300ft/s.
The most technologically advanced paintball marker is the electropneumatic. Here, the trigger activates an electronic microswitch (or more recently, a magnetic or optical sensor) and information is passed to a computer-controlled solenoid valve which releases the propellant to drive the bolt forward and fire the paintball. This microcontroller operation makes the marker operate very quickly, and allows for extremely high rates of fire. These markers are the most expensive and are generally used for tournament play where rates of fire can reach and exceed 30 balls per second.
There is also a strong following of stock-class and "pump" players who use markers with a purposefully low rate of fire and ammo capacity. Pump markers require the player to recock or "pump" the marker before each shot, and stock-class markers have even more limitations on rate of fire and paintball capacity.
Some markers are designed to look like real guns, such as the Tippmann markers X7 and Alpha Black (which looks like M16 and was developed by the U.S. Army), RAP4 which makes several versions of the T68 Paintball Marker (Which looks like a M4 Carbine, has an internal Air or CO tank and is magazine Fed), or Smart Parts that makes theSmart Parts SP8 (based upon the German Heckler and Koch Prototype XM8 as well as much of the Armotech product line). These markers are called mil-sim , short for military simulation. They are used almost exclusively in woodsball and military scenario games, though with a few modifications the markers can be competitive in the speedball arena. The more expensive mil-sim markers tend to be considerably more rugged than most high-end speedball markers, but are heavier and tend to operate at slower rates of fire. Most also feature camouflage or black coloring (rather than the bright colors found on tournament markers), since stealth is of more value in the woodsball environment than that of the much smaller speedball arena. Some mil-sim markers use hoppers, though some use magazines similar to real-life automatic weapons. Many come with a shoulder stock and use a coiled remote line connected to a tank of propellant usually carried on the players back, in order to follow the mil-sim look and to lighten the marker up and make it more maneuverable.
Mil-sim markers are not without controversy, however. There have been several incidents in which mil-sim paintball players have been reported to the police as carrying actual firearms. This is becoming a serious problem with local law enforcement in cities where there is high mil-sim paintball activity, especially if the games are hosted away from paintball facilities (e.g. at a player's estate or an "outlaw" paintball location). Since the markers are nearly identical to real firearms, law enforcement has difficulty discerning the differences between real-life weapons and their paint-shooting counterparts, which, in a pre-combat situation, can be hazardous since the time allotted to identify the alleged armed target is minimal.
Propellants
Paintball markers are powered by the expansion of gas stored in a compressed gas bottle. The two most common forms of compressed gas are carbon dioxide and high pressure air (HPA).
Carbon dioxide
Because CO 2 becomes a liquid when compressed, it must expand to a gas in order to be used by most paintball markers, although several older models actually require liquid CO 2 in order for proper operation. This expansion is not adiabatic and requires energy, causing the tank to cool as heat is used to expand the liquid CO 2 into gas. Eventually, under sustained fire, and especially in cold weather, the tank can become so cold that ice crystals form on it. If the CO 2 bottle does not have an anti-siphon tube fitted, or is shaken while firing, the liquid CO 2 may enter the marker. The liquid CO 2 then passes through the marker instead of the tank, evaporating and causing the marker to freeze. This results in large clouds of CO 2 vapor ejected from the marker upon firing, caused by the liquid CO 2 evaporating in/around the barrel. This is known as "drawing liquid". This can cause damage to internal seals and O-Rings, and can "freeze" some markers, putting it out of commission for some time while it warms back up. Simple operation designs such as in-line blow-back (most Tippmanns), guns designed before HPA was more widely used, or guns using 12-gram CO 2 powerlets are usually not affected by this problem, but it can still cause damage to the marker over time. For this particular reason, most high-end markers recommend that you use HPA. Technically, CO2 and HPA can propel the paintball, but when high rates of fire are attained, liquid is sucked into the marker which can damage or even destroy electrical components inside the marker such as the solenoid. Never leave a CO 2 container in sunlight, as the heat will cause the gas to expand to a dangerous level. The tanks include safety valves in their construction, but there is no need to use them or take unnecessary risks.
With normal back-bottle setups (or, air systems utilizing a horizontal air source adapter, more commonly called an ASA), the less dense gaseous CO 2 will rise to the top half of the tank. Normally, ASAs are angled slightly so the gaseous CO 2 is always available at the valve of the tank. Special devices known as anti-siphon tubes extend the mouth of the valve, and provide only CO 2 from the top part of the tank.
During rapid successions of shots, gaseous CO 2 is used up. Liquid CO 2 will take some time to evaporate and rebuild the internal pressure. This process causes potentially large changes in velocity and therefore, in accuracy and range.
High pressure air or N 2
When nitrogen or HPA (High Pressure Air) is compressed, it remains a gas. When it expands, it also cools the tank, due to the Joule-Thomson effect, but at a far lower rate than liquid CO 2 because it does not have to change from liquid to gas. The lack of this transition reduces the variation in pressure associated with rapid successions of firing cycles, improving accuracy. Therefore it is viewed as a superior source of propulsion.
However, because these propellants are stored at higher pressures (up to 5000 lbf/in² or 34 MPa) while liquid CO 2 is stored at around 1200 lbf/in² (8 MPa), tanks for nitrogen and HPA are more expensive and heavier. Modern designs are usually wrapped in carbon fiber or other composite materials, to allow for thinner walls (thus, lighter weights) while withstanding the greater pressure. Average pressure for HPA tanks used in paintballing is 31 MPa (4,500 lbf/in² or 310 bar). The tanks themselves can either be filled with pure N 2 or compressed air, which is 79% N 2 . These air sources have traditionally been used primarily by people who play often and have tournament-grade markers; however, they are becoming more popular among casual players.
105 in³ to 114 in³ (0.8 to 2 L). The 68 in³ (1.1 L) size is considered average. Smaller tanks may not last heated matches, while larger tanks are cumbersome and require mounting options that create a larger marker profile. Thus, large tanks are usually only seen in speedball back players, who do little movement but fire thousands of rounds in a game. Scenario players that fire a similar volume of paint will also utilize a large tank. 48 ci tanks are rarely seen, as a 68 is only slightly larger in form but offers a far longer play time.
HPA is also known as nitrogen, nitro, or N 2 . The reason for the varying name difference is because in the late 1980s and early 1990s, Tom Kaye and Team Nitro used large 114 cubic inch tanks on their back. This was the first team to use nitrogen in a paintball setting. The gas they used was 100% nitrogen, which is very rare today. The reason for this is that air compressors capable of filling tanks to the required 3000+ psi (21 MP