This Adams Arms EVO Ultra Lite Mid Length Gas Piston Upper Assembly is chambered in 5.56x45mm NATO and comes ready to fire right out of the box after installation onto any AR-15 lower receiver. Designed to be the ultimate lightweight solution for competitive, recreational or hunting purposes, the EVO Ultra Lite trims weight wherever possible while still maintaining excellent accuracy, long term durability and high performance. It does this by combining a melonite treated, 14.5" ultra-light contour barrel with a 12" extended Samson Evolution Modular Free Floating Handguard and a low profile piston gas block. The shooter's preferred sighting arrangement is easily accommodated by a continuous top picatinny rail interface that runs from the rear of the forged A3 flat-top upper receiver to the low profile gas block, while both recoil and muzzle climb are efficiently handled by an effective Adams Arms flash hider which is permanently affixed to the barrel. Additional features include a mid length gas system for a longer sight radius and smoother recoil impulse, complete bolt carrier group, charging handle assembly, one 4" modular rail section and two 2" rail sections.
The upper's barrel has been finished inside and out with Adams Arms' proprietary QPQ Melonite treatment that bonds with the metal on a molecular level. Also referred to as salt bath nitriding, this treatment 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 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.
All Adams Arms uppers feature a short stroke gas piston operating system, which prevents hot gas and debris from being directed back into the action upon firing. The result is a rifle that runs cooler, cleaner and more reliably than those utilizing a standard direct gas impingement system of operation. To ensure that damage doesn't occur to the buffer tube from carrier tilt, the bolt carrier is equipped with enlarged "skis" to help guide it into the receiver extension. The bolt carrier's solid steel, 1-piece construction incorporates an integral piston strike face to guarantee integrity over time, while the bolt assembly is spring loaded for proper lock-up and to help reduce bolt bounce and cam pin wear. All piston components are finished in QPQ Melonite for corrosion resistance and easy cleaning/maintenance.
- Upper Receiver Type: A3 Flat-Top, Forged
- Barrel Length: 14.5" with a permanently attached flash hider to extend the barrel to 16.1"
- Barrel Contour: Ultra Lightweight
- Barrel Material:4150 Chrome Moly Vanadium Steel
- Muzzle Thread Pattern: NA
- Chrome Lined: No
- Barrel Finish: QPQ Melonite / Black Nitride
- Twist Rate: 1 in 7"
- Chamber: 5.56x45mm NATO
- M4 Feed Ramps: Yes
- Muzzle Device: Permanently Attached Adams Arms Flash Hider
- Gas System Length: Mid-length, short stroke piston operated
- Gas Block Diameter: 0.625"
- Handguard: Samson 12" Evolution Extended Modular Rail, Free Float
- Sights: None
- Includes Two 2" and one 4" Picatinny Rail Sections
Please Note: Installation of AR-15 upper assemblies with certain features including, but not limited to: flash hiders, bayonet lugs, and threaded muzzles may violate state and/or local laws.