5" 5.56 NATO AR-15 Barrel – Ultra-Compact Performance for Tactical Builds
This 5-inch 5.56 NATO barrel is built for ultra-compact AR-15 platforms, offering lightweight maneuverability without sacrificing durability. It features a pistol-length gas system for reliable cycling in short configurations and a 0.750" gas block journal to accommodate most standard components. The 1:7 twist rate is ideal for stabilizing a wide range of bullet weights, especially heavier 62–77 grain projectiles commonly used in tactical and defensive setups. Made from 4150 CMV steel and finished in QPQ nitride, the barrel is resistant to corrosion and wear, even under harsh conditions. Threaded 1/2x28 at the muzzle, it’s compatible with standard 5.56/.223 muzzle devices, flash cans, or suppressors. With M4 feed ramps and a rugged profile, this barrel is perfect for PDW builds, truck guns, or any AR pistol designed for maximum control in close quarters.
Specifications:
Gas Block:
QPQ Black Nitride coated
.750 ID
low profile
4340 steel
light weight
1.6oz
Micro Gas Tube:
Stainless steel
Micro length
Info:
- Note- MLOK and Keymod Handguards are compatible with this assembly. M Lok nuts will clear Handguard directly under the gas block.
- Note- For Suppressed or Traditional muzzle devices use a 4.25? Handguard (Receiver to muzzle shoulder distance is 4.3?) or up to 5.0? Handguards if no suppressor to be used. ( Receiver to muzzle end is 4.95?)
- Note- For Linear Comps use a 5.5? to 6? Handguard. Generally we use a HG 1/2? longer than the barrel.
- Note- Usually H to H3 buffers are used. For PDW stocks we have used the Gorilla H2 ,H3 and Heavy types both seem to work the same.
AR Micro Gas System 1:5 5R Kit
The AR Micro Gas System 1:5 5R Kit | Black Nitride is a high-performance component designed for AR-15 and AR-10 platforms, offering superior gas flow regulation, enhanced durability, and optimized ballistics. Whether you’re a seasoned builder or new to the AR customization world, understanding the features and benefits of this micro gas system can help you make informed decisions for your firearm build.
What Is an AR Micro Gas System?
The AR Micro Gas System is a compact gas system that regulates gas pressure and cycling efficiency in short-barreled rifles (SBRs) and AR pistols. Compared to mid-length and rifle-length gas systems, micro gas systems are designed specifically for ultra-compact barrels, typically 5 to 7.5 inches long.
In traditional direct impingement (DI) AR-15s, gas is redirected from the barrel back into the bolt carrier group (BCG) to cycle the action. The micro gas system shortens this process, ensuring that gas regulation and cycling occur within a much smaller footprint, making it ideal for close-quarters combat (CQB) and compact firearm applications.
1:5 5R Rifling – What It Means and Why It Matters
The 1:5 5R rifling in this kit plays a crucial role in improving accuracy and bullet stability. In rifling terminology, 1:5 Twist Rate means the bullet completes one full revolution for every five inches of barrel length. This faster spin stabilizes heavier rounds more efficiently, leading to tighter groupings and enhanced ballistic performance. 5R Rifling differs from traditional rifling by using five lands and grooves instead of six, with angled lands that reduce bullet deformation and fouling buildup. This rifling design results in better accuracy, reduced barrel wear, and improved overall consistency in shot placement.For shooters who prioritize precision and performance, the 1:5 5R rifling combination offers superior stabilization, particularly when using match-grade or high-grain ammunition.
Black Nitride Coating – Durability and Corrosion Resistance
The Black Nitride finish applied to this AR Micro Gas System 1:5 5R Kit enhances its durability, corrosion resistance, and performance. Unlike traditional phosphate or parkerized coatings, black nitride chemically alters the surface of the metal, creating a harder, smoother, and more wear-resistant finish. Whether you're operating in dusty, wet, or high-temperature environments, the Black Nitride finish ensures that your micro gas system and barrel remain in peak condition for years to come.
How the AR Micro Gas System Affects Performance
The AR Micro Gas System 1:5 5R Kit is specifically designed to enhance firearm performance in short-barreled AR platforms. Since shorter barrels have reduced dwell time (the time the bullet spends in the barrel after passing the gas port), a micro gas system is required to compensate for the faster cycling rate.When comparing a Micro Gas System to other standard configurations, there are notable differences in how gas pressure is managed within the firearm.To fully take advantage of the 1:5 5R rifling, selecting the right ammunition is crucial. Since this rifling is optimized for heavier bullets, it performs best with high-grain, match-grade, and defensive rounds.If you're looking to build a compact, high-performance AR-15 pistol or SBR, the AR Micro Gas System 1:5 5R Kit | Black Nitride is one of the best options available. With its superior gas regulation, corrosion-resistant finish, and precision rifling, this system provides increased reliability, improved accuracy, and reduced recoil, making it ideal for home defense, tactical applications, and short-range engagements.
By investing in a high-quality micro gas system, you ensure that your AR-15 functions smoothly under demanding conditions, offering you the best combination of durability, performance, and shooting comfort. Whether you're a seasoned shooter or a first-time builder, the AR Micro Gas System 1:5 5R Kit is a game-changer for compact AR platforms.
