.300 Blackout AR 15 Side-Charging Rifle Kit – 16″ Stainless and Black Nitride Fluted Heavy Barrel, 1:8 Twist Rate with 12″ M-Lok Handguard

Please note: We strive to provide the most accurate photographs of our product wherever possible. Due to availability limitations and supply chain constraints, slight variations of the handguard of this upper assembly may occur in the aesthetics of the skeletonizations in between the M-Lok sections.
If the idea of building your own AR-15 chambered in .300BLK (.300 AAC blackout) has piqued your interest, then you’re not alone. If your aim is to build one with its own sense of style, then check out this .300BLK built kit. At its core is a 16-inch stainless steel barrel that’s been coated in black nitride and given bear claw fluting for that extra in-your-face flair. Plus, it’s side-charging, so your new creation won’t be boring. It’s also got a 12″ free-floating M-Lok handguard on which to mount your light, laser, or whatever else.
Plus, we give you most of the extras you’ll need to complete the whole kit. You get a mil-spec buffer tube assembly and butt stock that adjusts in the standard six positions and of course a mil-spec lower parts kit. Of course, top it off with the backup sights or optic of your choice. Please note, mags and ammo are not included.
What’s Included
This kit is not a firearm. It includes an assembled upper receiver, bolt carrier group, lower parts kit, and buffer assembly with buttstock. 
300 Blackout AR Kit Specs
Barrel

Chamber: .300 AAC Blackout
Contour: Heavy
Length: 16”
Twist Rate: 1:8
Gas System: Carbine
Gas Port: 0.750”
Gas Hole Dia.: 0.070”
Muzzle Threads: 5/8×24
Feed Ramps: M4
Material: 4150 CMV
Finish: Stainless Steel and Black Nitride
Process: Button Rifled
Lining: None
Extension: M4
Muzzle: A2 “Birdcage” Flash Hider

Handguard

Attachment System: 12″ M-Lok
Finish: Type III Hardcoat Anodized (Mil-Spec)
Top Rail: M1913 Picatinny
Material: Billet 6061-T6 Aluminum
Attachment: Barrel Nut 

Upper Receiver

Profile: M4 Flattop
Material: Forged 7075-T6 Aluminum
Finish: Type III Hardcoat Anodized (Mil-Spec)

Bolt Carrier Group

Profile: M16/Full-Auto
Steel: 9310 Tool, HPT/MPI-tested
Exterior: Black Nitride
Interior: Not Chrome-Lined
Gas Key: Staked, Chrome-lined
Charging Handle: Included

Lower Receiver Parts

Buffer System: Mil-spec, Carbine
Buttstock: Mil-spec, M4-type
Parts Kit: Mil-spec, single-stage

Lower receiver not included.

WARNING: Handling firearms parts and accessories can expose you to lead and other petroleum products known to the State of California to cause cancer and reproductive harm. For more information go to: www.P65Warnings.ca.gov

Shipping Restrictions
Shipping of various parts and/or accessories are prohibited to states and locales (ie New Jersey, California, New York, etc…) with restrictions against certain parts and/or accessories or “assault weapons” (i.e. states with high-capacity magazine restrictions, manufacturing of semi-automatic weapons, etc..). It is your responsibility to be aware of your local firearms laws before purchasing from our website or machining a firearm. We try our best to keep our shipping page current, but laws change daily.

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