American Made
Buy Machine Shop Direct
Need Assistance? Call us at 425.530.0837
18" 5.56 Socom Melonited 1/7 AR15 Upper w/ 12" HD Quad Rail Blem
On Target With
Savings Of
Original Price $329.99
Sale Price $169.99
While the 16 inch barreled uppers get all the attention these days the 18 inch upper is one of the best kept secrets of the AR15 rifle world. The extra length provides not only more velocity to the projectile headed down range but also more stability. Often times used for competition shooting this upper uses the extra barrel length of the 18" socom profile to step up to a mid-length gas system. The longer gas system reduces gas impulse while maintaining dwell time of the round in the bore giving a reliable but smooth recoiling feel to the rifle. Often times paired with an optional muzzle brake these uppers can provide some of the fastest follow up shots the AR has to offer while allowing flatter shooting at medium ranges. The profile of the 18" barrel is cut to a .750" profile under the handguard and in front of the gas block for reduced weight.

Why should I run a Hardened Arms quad rail?

Hardened Arms machines our quad rails in house from American 6061-T6 extrusions. This quad rail is free floated from the barrel providing better accuracy and no influence/pressure on the barrel. The handguard is attached directly to the barrel nut that holds the barrel in the receiver with 8x hex head button screws for secure mounting and easy maintenance. At 12 inches the vented handguard covers the gas system entirely and is machined to allow the addition of an endcap flush with the end as an upgrade. The full length picatinny rails allow attachment of many accessories at the 3, 6, 9 or 12 position from a bipod underneath to targeting lasers compatible with 1913 picatinny rails.

18" 5.56mm AR-15 Upper Receiver Assembly:

    Hardened Arms M4 Feed Ramp Flat Top Receiver
    Mil-spec 7075 Upper receiver
    Black anodized mil-spec finished upper receiver
    Feed ramps for increased feeding reliability on barrel and upper
    Laser etched T-Marked upper receiver
    4150CMV Mil-Spec-B Steel Melonited Barrel
    Chambered in 5.56mm (will also shoot .223)
    18" Socom Profile barrel with M4 Extension
    6-Groove, 1/7 twist button rifled
    .750" diameter at gas block
    1/2x28 threaded muzzle/barrel
    Low profile gas block
    Barrel dimpled to secure gas block
    Mid-Length gas system
    A2 flash hider
    12" Hardened Arms Quad Rail Hand guard (end cap available as an upgrade)

Fits any mil-spec AR15 lower receiver.
4150CMV Barrel Steel
Whether starting with our 4150CMV machine gun barrel steel or highly refined 416R stainless steel our barrels are a cut above the rest. Engineered for accuracy and durability they are double nitrogen stress relieved and sodium nitrate coated/melonited (raw stainless steel is polished with melonited extensions). Index pins that lock into the upper receiver are pinned into the barrel through the extension on melonited barrels meaning the extension will never come loose. Machined in house on state of the art CNC equipment we deliver a barrel with every spec carefully controlled for peak performance.
Rail Lock Free Float Handguard
Machining our handguards in house provides us the opportunity to integrate features not found on most rails in the industry. Our rail lock feature, is designed to dovetail around your upper reciever insexing to insure a perfectly aligned rail that extends over the end of the upper reciever enough to do away with the unsightly gap found on lesser quality rail to receiver match ups. Combined with 6061-T6 aluminum with class II type III, hard coat anodized finish to match our uppers, fit and finish are top notch. Hardened Arms has many rail styles to choose from that are both stylish and functional. Our handguard offerings include quad rails, reduced weight rails, ergonomic smooth rails, skinny competition rails and our innovative patented Lumashark(R) illuminated rail with high lumen lights built in. Hardened Arms rails come in a variety of lengths and choices to meet your mission specific needs. .
Attention to detail.
It's the attention to detail that sets Hardened Arms apart. Items such as our machined in house 'Jam Nut' ensure ease of changing muzzle devices and indexing flash hiders while being fully re-useable. Crush washers are a thing of the past as they are single use and can induce stress and cause problems if used improperly. Bull barrels use shims to time your muzzle device without adding to the diameter of the already rigid barrel.

Alignment dimples are also machined into your barrel at the same time the gas port is drilled to provide 100% accurate positioning of your gas block and to keep it securely in place in spite of recoil. We machine our gas blocks and adjustable gas blocks right here from 4150 US barrel steel to give you the strongest and most durable product possible..
Hardened Arms uppers are high end, accurate, head spaced, inspected and test fired prior to shipping. They are built using stringent specs, top quality parts and procedures to ensure maximum reliability and performance.

You are responsible for knowing your state laws regarding barrel lengths, pistol and short barreled rifle restrictions. 20% restocking fees if you cancel anytime after you order or can not take delivery due to state restriction. Dealer programs are available on our website. Two year warranty against manufacturer defects. Finishes will wear with use, no warranties apply to finish wear. Fits any mil-spec AR15 lower receiver.
515 Tucker Ave Friday Harbor, WA 98250 |
Phone: 425-530-0837