Bolt Gas Port

The bolt gas port, also known as the gas port, is a small hole or channel in the bolt carrier of a firearm. It is designed to allow gas from the fired cartridge to enter the bolt carrier and cycle the action of the firearm.

When a round is fired, the expanding gases from the ignited gunpowder travel down the barrel and into the gas port. The gas port directs these gases into the bolt carrier, where they exert pressure on the bolt, causing it to move rearward. This rearward movement of the bolt unlocks the chamber, extracts and ejects the spent casing, and loads a new round from the magazine into the chamber.

The size and location of the gas port can vary depending on the specific firearm design and intended use. It is an important component in the functioning of semi-automatic and automatic firearms, as it allows for the reliable cycling of the action.

It's worth noting that the gas port is typically found in firearms that use a gas-operated system, such as AR-15 rifles or AK-47 rifles. However, not all firearms have a gas port, as there are other operating systems, such as blowback or recoil-operated systems, that do not rely on gas to cycle the action.