Jam door

A jam door, also known as an access door, is a standard feature of clip system or electronic blasters. The jam door is a piece that slides back, allowing slight access to the internals in case of a jam. If a dart is jammed in the chamber, the user may remove it from there.

Details
The jam door is usually orange (in some blasters black, or in the Hail-Fire's case, clear) with holes scattered around it. Flip-open doors are made up of one piece held in by a metal bar, and can flip up/slide open to allow access to the chamber. Slide-open doors usually use a friction ridge to stay closed, but sometimes rely on the blaster's priming system. In slide-open blasters, if the door is left open while the blaster is being primed, it will close automatically as the bolt is moved forward. Some blasters may have more than one jam door, such as the CrossBolt. Normally, a blaster cannot fire without completely closing the jam door, however, some blasters such as the Revonix360, RaptorStrike, and SlingFire can function with the jam door open.

Modification
Modders sometimes choose to remove the jam door for even easier access to the chamber, other times, the jam door is not only removed, but is cut out in a way that will allow for darts to be loaded into the cut-out section.

Mechanical locks associated with the jam door (such as a lock that prevents the opening of one if the bolt is not in the rear) are often removed to allow the jam door to be opened at any time. Electronic locks that are linked to the jam door that prevent flywheel blasters from firing are usually also removed.

Unjamming button
An unjamming button, also known as a jam release button or jam release switch, is a component on some blasters that aids in unjamming.

On some blasters, unjamming buttons release the bolt sled's mechanical lock, even after the blaster is primed. This allows the bolt sled to be moved back for clearing jams. As such, these types of buttons are also referred to as prime-lock override buttons. Since unlocking the bolt sled prematurely may cause double feeding and more jams, these buttons may only be allowed to be engaged with a thin object such as a pen or paper clip.

On Vortex blasters, there is a jam release switch either on the side or back of the blaster that ejects a chambered XLR Disc to clear a jam.

A blaster may contain both a jam door and an unjamming button. In some ways, the unjamming button may supplement the jam door by permitting the user to move the bolt sled back, thereby allowing them to clear a jam through the jam door.

Trivia

 * Users of the Vortex blasters generally experience less jams than the typical N-Strike blasters. N-Strike Elite blasters also generally jam less than its predecessor line due to improved internals.
 * Depending on the shape of the jam door and bolt sled, with enough skill, a user could theoretically load a dart into the chamber through the door's opening, without removing the blasters' clip. However, this is very difficult to do and not very practical; a more plausible use would be to load darts into a blaster's clip mid-battle through the jam door, easily doable on some flywheel blasters.