Markers

Spoolers
In a Spool-valve-based electropneumatic marker, the bolt also acts as the valve. This eliminates the need for a stacked tube construction, and indeed spool valve markers are notable for their compact profile. Rather than employ a cycling hammer or ram that strikes a pin valve, the movement of the bolt is controlled entirely by the routing of air into small chambers in front of or behind the bolt. Additionally, there is an air reservoir behind the bolt that contains the air that will be used to fire the paintball. When the marker is at rest, air is routed to the front of the bolt to prevent any of the air in the reservoir from escaping. When the trigger is pulled, that air is either vented, allowing the air in the reservoir behind the bolt to simply push it forward (as is the case in an “imbalanced spool valve” design), or the air is rerouted to a small chamber behind the bolt (separate from the reservoir), which then pushes the bolt forward (a “balanced spool valve” design). In either case, the movement of the bolt forward exposes pathways in the bolt or the marker that allow the air in the reservoir behind the bolt to surge forward and fire the paintball.

A typical spool valve has at least one O-ring that undergoes a shear/compression duty cycle every shot, leading to faster wear and less reliability. Additionally, the necessity of an air reservoir makes them less gas efficient than their poppet-valve counterparts. However, since spool-valve markers feature no reciprocating mass (other than the bolt) and require little pressure to operate, they have less recoil and very little noise. Examples of markers that utilize this mechanism are the Dye Matrix, Smart Parts Shocker, and Smart Parts Ion.[3]

Poppets
Poppet-valve-based electropneumatic markers are very similar to mechanical blowback markers in that they feature a stacked-tube construction, built around a poppet valve, that is opened when struck by a force. However, unlike mechanical markers which provide that force with a hammer propelled by a spring, the valve in poppet-valve electropneumatic markers are activated by a pneumatic ram. In the same way that the bolt is connected to the hammer in mechanical blowbacks, the bolt in poppet-based electropneumatics is connected to the ram. Poppet-valve electropneumatics share the same disadvantages as their mechanical counterparts, namely external moving parts, a reciprocating mass, and a louder firing signature. However, they are also more gas efficient than spool-valve electropneumatics since the poppet valve only releases the precise amount of air needed to fire the marker. Examples of markers that utilize this mechanism are the WDP Angel, Planet Eclipse Ego, Bob Long Intimidator, and Bushmaster.

Blowback
The majority of mechanical markers employ a simple blowback system utilizing a poppet valve (also known as a “pin valve”), which is opened when struck by a compression force, provided in the form of a hammer propelled by a spring. These sorts of markers generally use a “stacked tube” design, in which the valve and hammer is contained in the lower tube, while the bolt, which is connected to the hammer, is in the upper tube (Some manufacturers, however, such as Tippmann, have managed to incorporate the valve, hammer, and bolt into a single tube, as exemplified in the Tippmann 98 Custom). The hammer is held in the back position, with the spring compressed, by a sear. When the trigger is pulled, the hammer is propelled forward by the spring, into the valve. The air released by the valve is then simultaneously channeled up to the bolt to fire the paintball, and back to push the hammer back into the cocked position (hence the name “blowback”).

Poppet valves are usually easy to replace and require little, if any, maintenance. The downside to this design, however, is its high operating pressure, which leads to a larger recoil and arguably less accuracy. Some markers, such as the Autococker, have a separate firing and recocking sequence, which decreases the recoil caused by the cycling of the hammer. Any marker with a hammer, however, has a significant firing delay when compared to a full electropneumatic.

Some markers are a hybrid of mechanical and electronic features. In these markers, the hammer and spring continues to activate the valve, but the hammer is released with an electronic trigger frame.

Blow Forward
The Automag uses a blow-forward operation. The idea behind it is to use a constant volume of air at constant pressure each shot, as to exert a constant amount of force each shot, resulting in great consistency. It is also relatively simple:

1. The trigger is pulled, the sear closes the on/off valve and releases the bolt a split second later.
2. Compressed air in the dump chamber overcomes the force of the bolt spring, pushing the bolt forward. As the bolt travels forward it seals off the feed port and 'uncorks' from the dump chamber. The compressed air from the dump chamber passes through the bolt and propels a paintball down the barrel.
3. Once the dump chamber pressure is vented down the barrel, the bolt is returned by a spring.
4. The trigger is released
5. The on/off valve opens and re-pressurizes the dump chamber
6. The dump chamber pushes the bolt forward, which is now held in place by the sear.
7. The marker is ready to fire again

The design was the original blow forward paintball marker. The design is also used in many other markers. Currently available new markers that use the blow forward system are the Tiberius Arms line of markers, and the ICD Freestyles. The spool valve marker is also derived from the blow forward operation.

Autococking
The Autococker is essentially a pump marker with an automated pumping mechanism. Like all pump markers, it is closed-bolt, and its operation can be broken down into two discrete phases, or cycles:

1) The Firing Cycle - The process that releases the gas that fires a paintball out of the marker is fairly simple compared to the re-cocking cycle. At rest, the bolt sits forward, closing the chamber (hence, closed-bolt). This prevents more paintballs from entering. A pull of the trigger drops the sear, which in turn releases the hammer. A spring propels the hammer forward into the valve, which causes the valve to release a burst of gas upward into the bolt. The bolt redirects the gas behind the paintball, propelling it out the barrel.

2) The Re-Cocking Cycle - Once the paintball is fired, three things must happen in order to return the marker to a "ready" state: 1) the hammer must be pulled back so that it re-engages the sear and re-compresses the spring, 2) the bolt must be pulled back so that another paintball can fall from the feed tube into the breech, and 3) the bolt must be pushed forward after the paintball is loaded to close the breech.
The Autococker back block

On both the Sniper and the Autococker, a back block performs all three of these functions. The bolt is attached to the block, while a cocking rod (which is attached to the hammer and designed to catch on the block) passes through it. When the block moves backward, it pulls the bolt back, allowing a paintball to drop into the breech. The backward movement simultaneously pulls the cocking rod back, causing the hammer to also be pulled back until it re-engages the sear. When the block moves forward, it pushes the bolt (and the paintball) forward, closing the breech. The cocking rod stays pulled back, with the hammer ready to fire.

A pump arm runs from the front of the marker to the back block and serves as the means by which the back block moves forward and back. The Autococker is distinct from pump markers in the means by which it causes the pump arm to cycle. In a pump marker like the Sniper, re-cocking is accomplished manually via the pump handle at the front of the marker. The pump handle, located beneath the barrel, is attached to the pump arm. When the player pulls the pump handle back, it causes the pump arm to extend and push the back block backward. Once the hammer is cocked and the paintball is loaded, the player then pulls the pump handle forward, pulling the back block forward. This cycle must be repeated after every shot.

Eyes
Many electro markers have "eyes" which are nothing more then light sensors that detect whether or not a ball is in the chamber ready to be fired or not. If it doesn't detect a ball, then it keeps the marker from firing so that it doesn't chop it.

Anti Chop Bolts
Anti chop bolts are usually on mechanical markers that don't have the benefit of being able to use eyes, but still want to provide the user with some kind of ball chop resistance. The way they generally work is the bolt moves forward, and if it doesn't find an adequate amount of resistance (like what a ball would provide) it quickly aborts the cycle and retreats. This keeps it from chopping balls that aren't fully chambered.

Fire Modes
Many electros have many different firing modes that include semi automatic, burst modes, fully auto modes and ramping modes. For the most part, all but semi automatic are usually banned at most fields. So having a marker that has a huge amount of firing modes is usually a dubious achievement.

Mech
A "mech" or "mechanical" marker is one that simply relies on no electronics. This is a very wide classification that can include non-electronic based autocockers, many inline blowbacks, and many blow forward markers.

Electro
Any marker with electronics in it can usually be considered an "electro." This includes what would normally be considered a mechanical marker that is operated via the use of a solenoid that puts pressure on the sear. Often electros will have multiple firing modes including semi, full auto, 3 shot burst modes, and ramping modes. However, many electric assisted firing modes (all but semi-auto) are banned from usage at fields as they violate a "one trigger pull, one ball rule." High volumes of fire are often misused and can cause injury on a paintball field, consequently, many insurance agencies force fields to enforce a semi-auto only policy.

Most electro owners gravitate towards electronic markers not for the vast array of firing modes, but their sensitive triggers. Many of the better ones feel as light as a mouse click, and can be walked (legally) via their double triggers at very high rates of fire.

Pump
Pump action markers must be manually re-cocked after every shot, much like a pump action shotgun. This manual action is much slower than other configurations, but is preferred by some over styles of markers as a challenge to themselves to learn how to play with less rate of fire. Others merely cite the increased satisfaction of playing with a pump. The slower pace of play also forces pump players to make every shot count, leading many to believe that the markers themselves are more accurate, which is not true, because the marker still moves from the pumping action. However, when properly modified, high end pump markers have been known to achieve extremely consistent velocities when chronographed.

Stock Class
Stock Class is a specific pump marker configuration that has the feed tube parallel to the breech requiring a tilting to load a paintball ( rock and cock). The stock class paintball gun is power by a single 12 gram CO2 powerlet that is held in place by a knob or housing that has to be completely removed to change the 12 gram powerlet.

Modified Stock Class was born to give those that have a standard pump paintball gun an opportunity to play stock. This configuration adds a 12 gram changer to the air system adapter and a 10 round vertical stick feed.