Paintballs, also simply called "paint", are spherical gelatin capsules containing primarily polyethylene glycol, other non-toxic and water-soluble substances, and dye. Paintballs are made of materials found in food items, and are edible but taste disagreeably. The use of polyethylene glycol (a laxative) in the fill can also cause gastrointestinal distress in indiv
iduals who eat a number of paintballs; therefore, they should be kept out of reach of young children. Early paintballs were made of glass and filled with inedible oil-based paint, since they were made for marking trees and cattle, but modern paintballs should easily wash out of most clothing. The color of the shell does not necessarily indicate the color of the fill.
Most common paintballs and paintball markers are described as .68 caliber, but many factors affect the exact dimensions. Paintballs and barrels vary in size from .67 caliber to .71 caliber. In addition, paintballs are seldom perfectly round and are very sensitive to heat and moisture. A hot or humid day may result in paint swelling or becoming misshapen.In addition if not used for a long time the paintballs (paint) will become hard.. Then should not be used for play,because the shell will not bust and will not mark the opponent. Care should be taken to keep paintballs out of the sun and away from moisture. An insulated cooler works well for this on the field. It is also a good idea to use your paint soon after you get it because the paint can settle making shots less accurate.
The gelatin shell of a paintball is designed to break upon impact, although ricochets or "bounces" may occur. There are many types of paintballs, including glow in the dark paintballs for use at night, scented paintballs, and formulations for winter play. When dropped on the ground, groundwater or condensation may swell the paintball, which could cause a jam in the barrel or rupture and foul the internal workings of the marker. Dropped ammunition is known as 'loose paint', and should not be used in a paintball marker.
Generally speaking, paintballs of greater price are subjected to more stringent manufacturing processes, quality checks, and standards, making their size and shape more consistent. This is very important for accuracy. Better paintballs also tend to have thinner shells to improve the frequency of breaking on impact rather than bouncing, and thicker, more opaque fills that are more visible and harder to wipe off.
While it is theoretically possible to freeze a water based paintball, the polyethylene glycol additive drastically lowers the freezing point of the mixture, making it highly unlikely to actually freeze it into something harder than a regular paintball. When introduced to a very cold environment, the paintball's shell will most likely dimple (making it less accurate) and the shell will become brittle. In fact, some professional speedball teams will cool their paintballs in a freezer to make the paint more brittle.
U.S. SWAT teams often use paintball-like balls, also known as a pepper ball, filled with Oleoresin Capsicum, the active ingredient of pepper spray, as a non-lethal incapacitation method. However, pepperballs are shot at a higher velocity than is safe for paintball (350+ FPS) and the shells are not made from gelatin, but rather a frangible plastic to make shots more painful for faster incapacitation. Pepperballs can be shot out of mostly any paintball marker.
A reusable ball is a foam substitute for a paintball, but is often used when describing "Reballs" and other brands of reusable paintball-sized spheres. Most reusable paintballs are the same size as normal paintballs, but weigh slightly more and do not contain a paint filling. As they do not break open to leave a paint mark on players, they are practical for indoor locations where accumulation of paint from broken paintballs would be a problem. This makes this form of paintball questionable, since no mark of paint is left, it allows players to cheat much more easily. A Reball is more expensive than a paintball, but since they can be cleaned and reused many times, they potentially have a lower cost per use. Some paintball parks have added dedicated reball fields, and some fields have actually gone exclusive with Reballs, eliminating the use of paintballs entirely. The primary use of Reballs, as intended initially by the manufacturer, is as a practice aid for teams who wish to save money by using reusable ammunition. Other manufacturers have created similar products, such as the V-Ball, a Velcro (hence the name V-Ball) reusable paintball. Reballs are also used at a lower velocity because of their inability to break on whoever they hit. For example, a Regular paintball will normally be shot at slightly less than 300 ft/s (91 m/s), while a Reball is supposed to be used at around 240 ft/s (73 m/s). It is noteworthy that the composition of Reballs results in increased ricochets, depending on the surfaces that they hit.
The term 'reusable balls' does not refer to paintballs that have been picked up from the ground