Ambush Firearms AR-15 Flat-Top Upper Assembly 5.56x45mm NATO 1 in 7" Twist 18" S2W Barrel Black Nitride Finish with MFR 12.0 Modular Rail Free Float Handguard, Shotgun Grip
The upper features a premium, cold hammer forged barrel made from mil-spec 4150 chrome-moly vanadium steel that is black nitride finished for durability and corrosion resistance, while both the bolt and carrier are subjected to a magnetic particle inspection (MPI) test to ensure a strong, defect-free product. The upper receiver is a flat-top design for compatibility with Picatinny-style optic mounts, and comes complete with M4 feed ramps, laser-engraved rail indexing marks, mil-spec bolt carrier group, charging handle, brass deflector and ejection port door.
The barrel has been finished inside and out with an advanced salt bath nitriding treatment that bonds with the metal on a molecular level. Also referred to as Melonite, this finish produces an extremely hard, slick surface on steel that resists carbon adhesion and increases corrosion resistance, extending a barrel's service life by reducing the friction produced inside the bore upon firing for a net decrease in bore surface wear over time. Nitriding converts the barrel steel's surface without any build-up, retaining all of the benefits of traditional chrome lining without suffering the accuracy degradation commonly encountered with it due to uneven application of chrome inside the barrel's bore. The end result is a barrel that's capable of producing accuracy on par with a match stainless steel tube, while also exhibiting the longevity and resilience of a chrome lined, mil-spec barrel.
The upper's MFR 12.0 Modular Rail Handguard provides multiple options for adding accessories, while also free floating the barrel for greater accuracy potential. With the exception of the full length, uninterrupted top rail, the MFR's slim and smooth exterior offers more user comfort than a quad-rail design, yet also allows for the installation of modular rail sections where desired for accessories. The 18" barrel features Ambush Firearm's signature Strength 2 Weight (S2W) contour for the perfect balance of barrel weight and stiffness, while the 5.56x45mm chamber is suitable for use with either 223 Remington or higher pressure 5.56x45mm NATO ammunition. Proudly Made in the USA.
- Upper Receiver: Flat-Top w/Case Deflector, No Forward Assist
- Barrel Length: 18"
- Barrel Contour: Strength to Weight (S2W)
- Barrel Material: 4150 Chrome Moly Vanadium, Cold Hammer Forged
- Muzzle Thread Pattern: 1/2"-28
- Chrome Lined: No
- Barrel Finish: Melonite / Black Nitride
- Twist Rate: 1 in 7"
- Chamber: 5.56x45mm NATO
- M4 Feed Ramps: Yes
- Muzzle Device: None, Thread Protector
- Gas System Length: Mid
- Gas Block Diameter: 0.750"
- Handguard: MFR 12.0 Modular Rail, Free Float
- Sights: None
- Extras: Low Profile Gas Block, 3 Modular Rail Sections, Shotgun-Style Forend
The total weight of the product, including the product’s packaging as it sits on our shelf. Since some products ship directly from the Manufacturer, their weight may be unavailable. Because of variations in the manufacturing process, similar products may have differing weights. Unless the product is designated as “Ships Alone”, Shipping Weight does not include the shipping box or packing materials associated with your order.
Product ships from MidwayUSA, separate from any other products on your order due to its size. Products that are Shipped Alone incur separate "Per Order" and "Per Pound" shipping charges.
Product is regulated by the US Department of Transportation (DOT) and cannot be shipped via USPS or air shipping methods. DOT-Regulated products must ship UPS Ground.
Product is restricted by shipping carriers and cannot be shipped to certain locations or via certain shipping methods.
Additional shipping charge for HazMat products. Carriers charge extra to ship packages with products they consider hazardous, such as reloading powder and primers.
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