Rifle Gas System Parts

Rifle Gas System Parts

A gas system of an AR rifle encompasses a gas block and a gas tube. The gas block fits over the barrel, typically replacing the front sight base, and is responsible for controlling the flow of gas from the fired cartridge back into the system, while the gas tube directs the gas from the gas block back into the firearm's action, causing the bolt to cycle.

Rifle Gas System Lengths

  • Pistol length gas system is used in AR pistols and some very compact SBRs (with a barrel fo 10 inches and shorter). It operates under high pressure, cycling the action quickly, but while this can lead to hard recoil and increased wear on parts, it's necessary for reliable functioning in compact firearms.
  • Carbine length gas system is the standard for most military M4 rifles and civilian AR-15s with shorter barrels (usually up to 16 inches). It offers a good balance between reliability and recoil, making it a popular choice for general use.
  • Mid-Length gas system is designed to work best with barrels that are around 18 inches long, offering smoother cycling and less recoil than the carbine system.
  • Rifle length gas system is intended for use with full-length, 20-inch barrels. This system provides the softest recoil and smoothest operation, but it requires a longer barrel to function reliably.

Now, an adjustable gas block allows you to adjust the amount of gas flowing into the system, enabling you to fine-tune your rifle's performance to suit different ammunition types or suppressor use.

AR-15 Gas Blocks & Gas Tubes

At GRITR Sports, we offer the best in AR-15 gas blocks & gas tubes, sourced from industry-leading brands. Whether you're looking for a lightweight low-profile gas block from 2A Armament, a dependable gas tube from Odin Works, a durable AR15 adjustable gas block from Aero Precision, or a high-quality gas system from Spike’s Tactical, we've got you covered. So why wait? Upgrade your AR-15 with top-notch gas system parts from GRITR Sports today!


What is an adjustable gas block?

An adjustable gas block allows you to control the amount of gas directed back into the rifle's action. This can help manage recoil, reduce wear on the firearm, and allow for customization based on different ammunition loads or suppressor use.

How do I choose the right size gas block?

The size of the gas block should correspond with the outer diameter of your firearm's barrel. Common sizes include .625", .750", and .936".

What is a low-profile gas block?

A low-profile gas block is designed to fit under a free-float handguard. They're typically used in custom builds where the user wants a longer handguard than the gas system length.