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10.5" 5.56 Upper w/ SDX (TM) Rail, Upper w/BCG & CH
On Target With
Savings Of
Original Price $469.99
Sale Price $299.99
Do you want a low profile pistol upper?

Built around our SDX (TM) Rail, this upper delivers one of the lowest profile handguards on the market. Perfect for a pistol/SBR or an entry type personal defense weapon. The ballistics of the 10.5" 4150CMV nitrogen stress relieved  we machine in house provides for accurate fire past 100 yards while giving you the size of an AR that will fit in the back seat of your vehicle. This upper in particular is a favorite of law enforcement for their entry teams and full auto builds.

Everything your pistol/SBR should be.

A staple at any full auto demo shoot for Hardened Arms this upper is designed to take a beating and come back for more. Running a 4140 chrome-moly steel barrel nut that has been QPQ'd for added surface rockwell this upper is almost bullet proof. Eating both brass and steel case ammo means you can train all day long without breaking the bank. Whether running a soul crushing muzzle brake or one of our Stingray 5.56 suppressors the handguard ends just back from the muzzle thread shoulder so your muzzle device will be clear of the end of the handguard. M-Loks cut into the rail at 3, 6 and 9 provides mounting room for all your accessories such a vertical foregrip a favorite among SBR shooters.

10.5" 5.56 SDX MkII 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
        4150CMV Nitrogen Stress Relieved 5.56mm Barrel
        Air-Gauged, Inspected and headspaced
        Chambered in 5.56mm (Will also shoot .223)
        10.5" Socom barrel with M4 Extension
        .750" barrel diameter at gas block
        1/2x28 threaded muzzle/barrel
        Low profile gas block
        Barrel dimpled to secure gas block
        Carbine-Length gas system
        A2 flash hider
        10" SDX (TM) Hardened Arms Slim Line M-Lok Rail (1.46" Cross Section, 1.3" Inner Diameter)
        w/ BCG & CH

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