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The Rough Cut 2x4's priming mechanism.

A priming mechanism, sometimes shortened as priming mech, is an internal mechanism seen on all non-battery-operated blasters.


As its name would suggest, priming mechanisms are involved in the priming process of a blaster, readying it to be fired. There are many different versions of priming mechanisms, and the mechanism used differs from blaster to blaster.


There are various modifications that can be performed on a blaster's priming mechanism, such as adding material for a better grip. Conversions can be performed on some blasters, making a blaster have a different priming style altogether; this is more traditionally done to transform bolt-action blasters to pump-action, through a homemade or 3D-printed converter.

For hammer-action blasters, there are metal aftermarket replacement hammers that can replace the stock hammer, and usually come with a replacement catch as well. They are more ergonomic and durable than the original plastic hammers.

Types of priming mechanisms


The SledgeFire, an example of a break-action blaster.

Break-action, also known as hinge-action, is a priming style that involves the blaster "breaking" open, creating two halves of a blaster or barrel. Darts are loaded inside one of these halves, and it is folded back up into place and ready to fire them.

Some blasters, such as the Nerf Lynx SD-1, ShellStrike DS-6, or the X-Shot Vigilante appear to be break-action, but have a separate means of priming (such as pump-action or slide-action).


The Longshot CS-6, an example of a bolt-action blaster.

Bolt-action, also known as straight-pull, is a priming style involving a bolt, usually located on either side of a blaster, being pulled back and pushed forward. Bolts may be packaged separately from a blaster, to be assembled before use; with some exceptions, bolts are not designed to be detached without modification. Some, such as the Nerf Helios XVIII-700, have bolts that can be attached to either side of the blaster, to be compatible with both right-handed and left-handed people.

Many bolt-action blasters have a "sniper" style to them, and may even be advertised as such.


The Jupiter XIX-1000, an example of a turn-bolt-action blaster.

Turn-bolt, also known as turn-pull or rotating-bolt, is a variant of the bolt-action priming style. It is not as common as standard bolt-action, and requires the bolt to be flipped upwards before priming and locked back down after priming. Blasters with a turn-bolt system only feature a bolt on one side.

The only turn-bolt-action Nerf blasters are the Jupiter XIX-1000 and PHARAOH. This style is also common with non-Nerf brands, such as the Buzz Bee Predator and the Adventure Force Alpha Rogue.


The Signature Bow, an example of a bow-action blaster.

Bow-action is a priming style that operates like a bow, where the user pulls back the mechanism and releases. Due to the simplistic nature of the priming action, bow-action blasters often lack a firing trigger; they are usually string-powered or feature a plunger that fires with drawn-in air pressure.


The Diamondista, an example of a crossbow-action blaster.

Crossbow-action is a variant of the bow-action priming style. Similar to bow-action, crossbow-action blasters require the user to manually pull back a blaster’s string to prime it, hooking it into place, which is released by pulling a firing trigger. The string runs horizontally, rather than vertically like traditional bow-action blasters.


The SlingStrike, an example of a slingshot-action blaster.

Slingshot-action is a variant of the bow-action priming style. Similar to bow-action, it requires the user to pull back and release a string or cord. However, unlike traditional bow-action, slingshot-action blasters usually feature a "striker" piece attached to the string, which snaps against ammunition and propels it forward.


The Voidcaster, an example of a dual-action blaster.

Dual-action, also known as double-action, is a priming style involving a single trigger operating as the priming and firing actuator; often, these are larger and longer than a standard firing trigger. Dual-action blasters are often advertised as requiring no priming, thanks to the dual-nature of the trigger. As it is serving two purposes, dual-action blasters have a heavier trigger pull and weakened firing power.

Some blasters, such as the Nerf Snapfire 8, have different "modes" that can be switched between, to adjust the blaster's spring and performance, for stronger, slower use or for lighter, faster use.

Dual-action blasters are very easy for dual-wielding, as only one hand is required to operate the entire blaster, reloading notwithstanding.


The Negotiator, an example of a hammer-action blaster.

Hammer-action, also known as single-action, is a priming style involving a hammer, usually located on the rear of the blaster. It is very effective for dual-wielding, as only one hand is required for both firing and priming a blaster.


The SlingFire, an example of a lever-action blaster.

Lever-action is a priming style involving pulling back and pushing forward a lever, similar to bolt-action. These levers are often located under the grip, but can also be located on the side of the blaster. Due to the location of these levers, lever-action blasters often do not feature any slam fire capabilities.

Certain lever-action blasters can be dual-wielded, due to the location of the lever. The Nerf SlingFire's lever is built into its handle, making it effective for use with one hand.


The Breakflip, an example of a flip-action blaster.

Flip-action is a priming style similar to lever-action, where a blaster's main handle is pushed forward and pulled back in order to prime a blaster. In comparison to lever-action blasters, flip-action ones are more compatible with being slam fired, as the user does not move away from the trigger as the blaster is fired. Like lever-action blasters, flip-action blasters can be primed with one hand, and as a result can also be dual-wielded.


The Atlas XVI-1200, an example of a pump-action blaster.

Pump-action is a priming style involving the user pulling back and pushing forward a slide or grip. This mechanism is usually located underneath the blaster, far in front of the firing trigger. Due to the simplicity of pump-action, as well as its usual location on a blaster, it can be one of the fastest priming mechanisms. This favors the pump-action style for blasters with slam fire, in order to achieve higher rates of fire.

Pump-action is the style used most frequently on air-powered blasters that lack a plunger system, in order to fill an air tank or bladder quickly. As a result, air-powered blasters often require more than a single pump in order to fully prepare a blaster for use.

It is also commonly used on HAMP-style blasters, that lack a trigger and fire solely through the pump-action nature of the priming mechanism.

Pump grip

The TwinShock, an example of a pump-action blaster with a vertical grip.

Pump grip-action is a variant of the pump-action priming style. This style features a vertical or otherwise-shape grip, rather than a traditional horizontal one. The position and style of this grip makes it easier to slam fire. Some may also have an adjustable grip, such as the Nerf Doominator.


The Missile Launcher Stock, an example of a stock-action blaster.

Stock-action is a variant of the pump-action priming style. This involves the priming handle or grip being built into an extending or retracting shoulder stock (or otherwise rear-positioned priming piece.) While it has little in common with traditional pump-action, it still retains the "pumping' movement required to prime a blaster.


The Disruptor, an example of a slide-action blaster.

Slide-action is a priming style involving pulling back and pushing forward a top slide piece. Some slide-action blasters have a return spring built into their priming mechanism, removing the need to return it to a forward position manually. In comparison to pump-action, slide-action may be a bit slower, due to the location of the slide.


The IonFire, an example of a breech-loaded and primed blaster.

Breech-action is a variant of the slide-action priming style. It involves a blaster having a breech, which slides backwards and reveals where darts are loaded; the priming mechanism is built into this breech cover. Blasters with a breech-action mechanism feature similarities to the way the clip system chambers darts, as they have not only the cover slide (a jam door, in a clip system blaster), but also a dart tooth.

Breech-action has been criticized for poor performance, as some blasters may cause darts to warp and bend when they are loaded.

Plunger rod

The Trilogy, an example of a plunger rod slide-action blaster.

Main article: Plunger rod

A plunger rod is a variant of the slide-action priming style. This features an external plunger rod, which is pulled back and locked into place. This is connected straight to the blaster's internal plunger system and head. As such, plunger rods either extend out the back of a blaster, or down the blaster's handle, depending on how the plunger tube itself sits inside.

Most plunger rods have a hole or hook to pull back with a single finger, or have two small handles to prime with two fingers. Due to the fact that the priming mechanism is wholly external, plunger rods also serve as a visual priming indicator.

Blasters with a plunger rod can be fired through a faux "bow-action" method, where the user releases the rod before it locks into place for firing.


  • An acceleration trigger can be considered the priming mechanism-equivalent of flywheel blasters.
  • The correct term for the action of priming a blaster would be to "cock" or "charge" the blaster. However, the term "prime" is technically not erroneous, because in blasters, the action of "priming" usually generates the power required to fire the projectile, rather than purely chambering a new projectile.
    • Some blasters' packaging refer to the method of priming as "cocking" as well. The Stockade's packaging markets the blaster as a blaster that does not require "cocking", as the blaster is semi-automatic.
  • In real firearms, slide-action and pump-action are used synonymously when referring to an underhand charging mechanism.