E

Effective length: n.The portion of a barrel's length from the breech to the beginning of porting. This is the length of barrel in which the propellant gas can expand and add velocity to the paintball. One frequently cited experiment indicates that the optimum effective length of a paintgun barrel is between eight and twelve inches. Beyond this length the gas has maximally expanded and may actually begin to cause drag upon the paintball, thus lowering efficiency and decreasing the number of shots the gun gets on one fill.

Elbow: 1. n. An angled angled tube (usually plastic), one end of which is fastened to the gun's feed neck. The other end of the tube is pointed upwards and receives the hopper or agitator. An elbow is usually required on a gun on which the feed neck does not point straight up. Elbows are usually classified based on their diameters (what size feed neck will the end of the elbow fit?).
2. n. A type of air fitting. An angled tube (usually metal) through which gas flows. They are typically used to force sharp changes in the direction of flow in places where a micro-line or steel braided hose would become pinched. Elbows are threaded so that they can be connected to other parts of the air system. Elbows are usually classified based on their diameters, angle (45 degree, 90 degree, etc.), and pressure rating.

Eliminate: v. A person who is struck by a paintball which breaks (or has been barrel tagged) is eliminated, must stop shooting or speaking to his teammates, and proceed to the dead box. Referees will also eliminate a player for cheating or other infractions.

Expansion chamber: n. An expansion chamber serves as a heat exchanger and conducts heat energy from the environment to the propellant system, expanding the gas or in the case of CO2 converting liquid in the system to a gas. Expansion chambers are practical only in CO2 driven systems since CO2 is temperature sensitive whereas high pressure air is not. Expansion chamber improve consistency in CO2 driven paintguns.

Eye: n. An eye is a sensor that is connected to the breech of the marker. The eye looks for a paintball in the breech. If it does not sense a paintball, it will not allow the marker to fire until it does. This virtually eliminates chopping. Eyes are only found on some electronic markers, generally not mechanical markers.