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16" 6.8SPC II- HBar-1/10- Middy HD Quad
On Target With
Savings Of
$154.00
Original Price $369.99
Sale Price $215.99
Hardened Arms LLC is pleased to announce the arrival of the Ultimate 6.8 SPC II upper for the AR-15 platform!  Custom machined in-house using the very best US steel, we use 4150 CMV  to create a stress relieved, air gauged and hand polished precision barrel for your upper. The barrel is coated with Melonite which is 3 times stronger than chrome and extends the life of your upper and increases accuracy due to its ability to penetrate and strengthen the steel without affecting the bullets path.  We run a 1:10 twist to stabilize the heavier 6.8 SPCll ammunition which affords a higher accuracy return. The 6.8SPCII caliber is a great round for longer range hunting on the AR15 platform. Often referred to as the 300 Blackout's big brother, it reaches out with real stopping power for those 300 to 500 hundred yard shots.

AR15 6.8 SPC II- Upper Receiver Assembly:

    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
    4150CMV 6.8 SPC II  Barrel
    Melonited Finish
    Stress Relieved for superior accuracy
    Chambered in 6.8 SPC II
    16" HBAR Profile barrel with M4 Extension
    1:10 twist
    .750" barrel diameter at gas block
    5/8x24 threaded muzzle/barrel
    Low profile adjustable gas block
    Barrel dimpled to secure gas block
    Mid- length gas system
    A2 flash hider
    12" HD Quad Rail rail (End cap option is available)


Fits any mil-spec AR15 lower receiver.

Hardened Arms 6.8 SPC II AR15 uppers are 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. Since we are the manufacturer we can hold tight tolerances to make sure you get the best quality at factory direct prices.


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