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18" 6.5 Grendel Melonited 12" HD Quad Rail Upper
On Target With
Savings Of
$80.00
Original Price $339.99
Sale Price $259.99
A 18" 6.5 Grendel machined from Mil-B Spec 4150CMV and melonited delivers the accuracy potential of this cartridge in a light weight package ideal for hunting and mixed range tactical engagements. The flat trajectory, high feet per second velocity of the round lends it self to hunting medium game or tactical situations at range. Our 12" tactical quad is machined here in our factory to give you the best fit and Type III, Class 2 anodized finish.

Hardened Arms machines your 6.5 Grendel in-house to the highest standards, utilizing US 4150 Chrome Moly Venadium steel, profiled and chambered to create an extremely accurate 6.5 Grendel upper for your AR15. Finished with Melonite/black nitride to give you years of durability and good hunting. 

When Ordering please note that the 6.5 Grendel requires a 6.5 Grendel Type II bolt for proper headspacing (5.56mm & 7.62x39mm BCGs will not function properly).

AR-15 6.5 Grendel Barreled 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
  • 4150 CMV Nitrogren Stress Relieved Barrel Machined In House
  • Melonite Finish
  • Chambered in 6.5 Grendel
  • 18" Socom Profile barrel with M4 Extension
  • 6-Groove, 1/8 twist button rifled barrel
  • .750" diameter at gas block
  • 5/8x24 threaded muzzle/barrel
  • Low profile gas block
  • Barrel dimpled to secure gas block
  • Mid-length gas system
  • Thread Protector
  • 12" HD Quad Rail without end cap

Available Bolt Carrier Group Package (Add On Option) :

  • 6.5 Grendel melonited BCG 
  • Mil-Spec Charging Handle
  • ASC 10rd 6.5 Grendel Magazine

Fits any mil-spec AR15 lower receiver.

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.Fits any mil-spec AR15 lower receiver.
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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