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Rainier Arms Mountain MOD3 Series 5.56 NATO AR-15 Threaded Barrel
The Mountain MOD3 barrel is Rainier Arms’ option for shooters seeking durability and heat resistance through nitrided 4150 CMV construction, without the weight or cost of fluted variants. While not as heat-rejecting as our fluted options, these barrels remain excellent for general purpose use and budget minded builds. Rainier barrels are machined with precision and feature hand-cut chambers and crowns for quality and consistency. There are no shortcuts—Rainier aims for perfection.
Specifications for Rainier Arms Mountain MOD3 Series 5.56 NATO AR-15 Threaded Barrel include nitrided stainless style construction (per model), Carbine Length gas system, 1/2x28 threads, and a .750 in gas block journal size. Available lengths include 12.5 in and 10.5 in variants with weights listed per model. Package contents include the Rainier Arms Mountain MOD3 Series barrel and AR-15 compatibility with AR platforms.
Specifications for Rainier Arms Mountain MOD3 Series 5.56 NATO AR-15 Threaded Barrel:
- Manufacturer: Rainier Arms
- Color: Black
- Fabric/Material: Stainless Steel
- Caliber: 5.56x45mm NATO
- Gas System Length: Carbine Length
- Gas Block Journal Size-Diameter: .750 in
- Threads per Inch: 1/2x28
- Barrel Material: Stainless Steel
- Flutes: No
- Gun Make: AR Platform
- Gun Model: AR-15
Package Contents: Rainier Arms Mountain MOD3 Series 5.56 NATO AR-15 Threaded Barrel
What firearm models is it compatible with? AR-15
Specifications
- Manufacturer:
- Rainier Arms
- Category:
- barrel
- Caliber:
- 5.56x45mm NATO
- Platforms:
- AR-15
- Weight:
- 25.8 oz (1.61 lbs)
- Length:
- 12.5"
- Estimated velocity:
- 2,450-2,825 fps
- UPC:
- 744985352869
- MPN:
- RABCMV556125MNFBLK
- Required Component:
- Yes
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• Complete assembly ready to use
• Multiple components included
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