Pistons

The piston is another extremely important part through which the spring passes. It is made of plastic or metal

•     Metal pistons used to be used because of their durability, but it has been proven that in basic ZnAl mechaboxes they suffer tremendous damage due to their heavy weight. Therefore, the use of these pistons is not recommended, or alternatively, they can be used in CNC mechaboxes made of aerospace grade duralumin
•     Plastic ones are the most popular among players. They are lightweight, do not damage the mechaboxes and also cheap. They can also be lightweight for high cadence weapons.

The piston body is fitted with teeths. These teeth catch the teeth of the wheels and cause the piston to stretch. The last tooth is filed down so that it does not interfere with the shot.  For most AEGs, pistons with 14.5 teeth are most commonly used.

According to the number of metal teeth, pistons are divided into:

    Full tooth

    In this piston, the entire tooth ridge is made of steel.

    Half-geared

Here 50% of the teeth are plastic and 50% are metal

    With a few metal teeth

    Most often this will be a basic piston where the first, so called "ramp tooth" is metal and the rest are plastic.

Plastic teeth have advantages and disadvantages:

•     Plastic ones have the advantage not only of low production cost, but also in the situation of piston jamming, when these teeth are damaged by the wheels, but there is no damage to other parts in the mechabox
•     Metal teeth are very durable, but in case of a jam they will not grind and there is a risk of serious damage to the inside of the mechabox.

In case of damage to the piston teeth, there is the option of buying only a new piston comb instead of the whole assembly.

The advantage of pistons is their great versatility. They can be used in various weapons practically without modifications, but there are exceptions in the form of special pistons. These can be tied to a specific set of wheels ( called a half teeth), or to use a DSG wheel that has a smaller number of teeth.

There are also special pistons for specific guns, which can then have a larger number of teeth due to their length, for example, 19 tooth pistons are used for SR25 type guns