AR-15 Gas Systems
The AR-15 rifle is a gas-operated weapon system that relies on the pressure of gasses created and expelled on firing to make the system cycle.
In a gas impingement system, the primer ignites the powder inside the casing creating an explosive reaction that produces heat and pressure. Hot gasses force the bullet from the casing neck, down the barrel. The energy and pressure created by that explosion not only propel the projectile downrange but when properly harnessed, operate the system through the following cycle:
The Gas block captures a share of the pressurized gasses and sends them back through the gas tube to a key port in the bolt carrier group. This forces the bolt carrier group backward. As the bolt carrier group retreats, the spent shell is ejected and replaced as the bolt carrier group returns to its starting position.
Parts of an AR-15 Gas System
The AR-15 gas impingement system is a simple system with relatively few components. The main components are the gas block, gas tube, and gas key.
Gas Block
A basic gas block functions as a gathering and routing station for gasses expelled through a small hole in the AR-15 rifle barrel. There are several different styles and profiles of gas blocks, but they have the same goal. Collect gasses from the barrel and send them back to the bolt carrier group by releasing them through the gas tube attached to the block.
Gas Tube
The gas tube in an AR-15 gas impingement system attaches to the gas block at one end and the gas key at the other. It provides a secure path for gasses to travel back to force the bolt carrier group to cycle.
Gas Key
The gas key is a fitting which the gas tube attaches to. It allows the gasses forced back from the barrel and gas block to enter the receiver and cycle the bolt carrier group.
Things to Consider When Buying AR-15 Gas System Parts
Depending on the length and intended use of your AR system you will need to choose appropriate gas system parts. A basic weekend range system or home defense setup is a very different creature from an ultralight competition rifle. Specialized gas system components are available for the needs of every shooter, and Wing Tactical offers many of the best. The efficiency and ability of your system to cycle properly are dependent on the proper function of your gas system.
Gas Block Type
There are many different gas block offerings for the AR-15 platform, and each of them offers a unique solution. Gas blocks are commonly available in forward site base, normal height, low profile or adjustable
- Forward Sight Base: These high volume gas blocks feature an integrated forward sight base and often a sling swivel. It’s an old school, familiar design for those who are accustomed to military-style setups.
- Normal Height: Normal height gas blocks are usually high volume gas blocks. These gas blocks often limit the shooter to a shorter handguard since they are tough to fit under a forend.
- Low Profile: Compact gas blocks that are designed to fit under handguards. These are often lightweight or adjustable as well as being smaller than standard height gas blocks. The smallest among these offerings may be labeled as micro gas blocks.
- Adjustable: Adjustable AR-15 gas blocks are often used by precision shooters to tune their gas systems. Gas tuning allows the shooter to maximize the performance of his system while controlling the negative effects of over gassing. Precision gas tuning is also a practice of shooters who may use different types of ammunition or compete at different elevations as changes in gas pressure can affect performance in both cases.
Gas Tube Length to Match your AR-15
Aside from the diameter of your gas tube, the only other real concern in fitting the gas tube for your AR-15 system is the length of the gas tube. There are four common lengths of gas tube for you to choose from. Pistol, Carbine, Mid-length and full or rifle length gas tubes are readily available from Wing Tactical.
Common Lengths of Gas Tube
There are four common lengths of gas tubes. A pistol length system, the distance between the receiver key and gas block is four inches. A Carbine system is seven inches. A Mid-length is 9-inch tube span and a full-length rifle gas tube is 12 inches. It is worth noting, that the overall barrel length of a system may vary, but these gas system measurements remain consistent.
Shop AR-15 Gas System Parts with Wing Tactical
The team at Wing Tactical is here to help. Wing partners with only the best manufacturers in the industry. Choose an adjustable gas block from JP Enterprises, the Fortis low profile gas block or even a 2A Ultralight Titanium gas block, Wing Tactical has them all and so many more you might find it hard to choose.
Don’t hesitate to contact the customer service department at Wing Tactical. Our site is staffed by people who are familiar with the products we sell. They are operators and armorers just like you and they’re happy to help you choose the right gas system parts so that you can truly Give Yourself an Edge with products from Wing Tactical.
Updated March 23rd, 2020