16″ AR-15 Barrel — 416R Stainless, 1:8 Twist, M4 Profile (5.56 NATO)
Overview
This 16″ AR-15 barrel is machined from premium 416R stainless steel and button-rifled for consistent accuracy and long life. Finished to Mil-spec tolerances with an M4 profile and M4 feed ramps, the barrel features a 1:8 twist optimized for stabilizing a wide range of 5.56/.223 bullet weights. With a carbine-length gas system, 1/2-28 muzzle threads, and dimpled gas journal for secure gas block installation, this barrel is an excellent choice for durable service rifles, precision carbines, and duty builds.
Key Features
- Caliber / Chamber: 5.56 NATO (also shoots .223 Remington)
- Barrel Length: 16″
- Material: 416R Stainless Steel
- Rifling: Button rifled for consistent bore finish and longevity
- Twist Rate: 1:8 — versatile for 55–77 gr bullets and match loads
- Profile: M4 contour with M4 feed ramps
- Gas System: Carbine-length for proven reliability
- Gas Journal: .750″ (dimpled for set-screw gas blocks)
- Muzzle Threads: 1/2-28 — accepts most brakes, compensators and flash hiders
Why this barrel?
416R stainless offers excellent corrosion resistance and a fine, durable bore surface that suits both service and precision use. The 1:8 twist is a true all-rounder — stabilizing light 55 gr projectiles as well as heavier 69–77 gr match bullets. Button rifling produces a smooth bore finish and consistent accuracy while remaining cost-effective compared with other stainless finishing methods.
Compatibility & Build Notes
- Designed to fit standard AR-15 upper receivers and barrel nuts.
- Dimpled .750″ gas journal fits common .750″ set-screw gas blocks — confirm gas block model for exact fitment.
- Use carbine-length gas tube and appropriate muzzle device for optimal gas timing and recoil characteristics.
- Professional installation & headspace check recommended for custom builds.
- Always verify local, state and federal regulations before assembling or modifying firearms.
Finish & Maintenance
Stainless barrels resist corrosion and are easy to maintain — regular bore cleaning after shooting and a light oiling of the exterior will preserve finish and accuracy. If you prefer a matte appearance or additional hardness, consider compatible coatings or treatments available on our site.
Pair With These Mid State Firearms Components
- Browse other 5.56 / .223 barrels
- .750″ gas blocks & mounting hardware
- Compatible handguards & accessories
- Contact Mid State Firearms for fitment or build advice
Quick Specs
| Caliber / Chamber | 5.56 NATO (.223 compatible) |
| Barrel Length | 16″ |
| Material | 416R Stainless Steel |
| Rifling | Button rifled |
| Twist Rate | 1:8 |
| Profile | M4 contour (M4 feed ramps) |
| Gas System | Carbine |
| Gas Journal | .750″ (dimpled) |
| Muzzle Threads | 1/2-28 |
Note: If you require a different gas journal diameter or a non-dimpled journal for clamp-style gas blocks, please contact Mid State Firearms or include your preference in the order notes.
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sound of freedom – This was a great set up. I loved being able to customize the set up. Only issue I had was my own fault as a newb to building these. I used a heavy barrel in a slim hand guard. It makes adding attachments tough with clearances. Hoping someday to also get an AR10 from here.