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16" 5.56 SS Spiral Fluted 1/9 Socom 10" Tac Quad Upper
Your Price $469.99
Looking to improve your range trips? Want the absolute most rigid and harmonically resistant barrel? A bull barrel delivers superb accuracy by increasing rigidity, decreasing harmonics and dramatically reducing felt recoil. These barrels are made in house on our state of the art CNC equipment, using only the highest quality stainless steel. Stress relieved 416R that has been air gauged and turned on centers delivers phenomenal accuracy when paired with match ammo. Upper comes with a stainless thread protector, optional muzzle brake available or add your own 1/2-28 threaded muzzle device later. 

AR15 Upper Specifications:
    Hardened Arms M4 Feed Ramp Flat Top Receiver
    Black anodized mil-spec finished upper receiver
    Feed ramps for increased feeding reliability on barrel and upper
    Laser etched T-Marked upper receiver
    416R Stainless Steel 5.56mm Barrel
    Air-Gauged, Inspected and head-spaced
    Socom Profile
    Spiral Fluted for increased cooling and weight reduction
    Chambered in 5.56mm (Will also shoot .223)
    1/9 Barrel twist
    .936" barrel diameter at gas block
    1/2x28 threaded muzzle/barrel
    Low profile gas block
    Barrel dimpled to secure gas block
    Carbine-Length gas system
    Stainless steel thread protector
    10" Tactical Free Float Quad Rail

Fits any mil-spec AR15 lower receiver.

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. A 20% restocking fee will apply if you cancel anytime after ordering or if you 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.
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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 | sales@hardenedarms.com
Phone: 425-530-0837