MK1 CQB 11.5″ Upper .223 Wylde (Fluted Barrel)

Experience superior tactical performance, engineered precision, and exceptional reliability with the MK1 CQB 11.5″ Upper .223 Wylde (Fluted Barrel). Crafted to exact industry standards, this product delivers uncompromised durability and effectiveness in the field.

Features & Performance Overview

The MK1 CQB 11.5″ Upper .223 Wylde (Fluted Barrel) is designed for tactical operators, target shooters, and firearm enthusiasts seeking peak functionality. Every component undergoes rigorous testing to guarantee durability, smooth operation, and optimal safety.

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Detailed Product Description

Griffin Armament’s MK1 Upper offers premium features and reliability to each user and allows end users to configure their upper to fit their needs. Standard and available features:

The Griffin HEDP™ Barrels provide High Endurance Dual Purpose functionality- offering high durability and precision accuracy. Nitrided 416R stainless steel provides the highest possible hardness and longest throat life available with match grade bore dimensions and bore finish. HEDP barrel bores are hand lapped, ensuring batch to batch consistency and accuracy. TRUE-BORE™ concentric suppressor grade threads provide an optimized thread interface for your silencer regardless of brand or model. M4 feed ramps and chambers are polished prior to nitriding for smooth reliable feeding, chambering, and extraction. Gas ports were carefully engineered to provide reliable function suppressed or unsuppressed with 5.56 NATO ammunition. M4A1 contour diameter between the chamber and gas block for minimal POI shift with suppressors and maximum accuracy and durability while maintaining field weight.

Features

• 416R SS barrel manufactured from stress relieved certified barrel steel
• Black nitrided for extended service life
• Magnetic particle inspected
• Button rifled
• 223 Wylde chamber for optimal accuracy
• Carbine length gas for softer recoil characteristics
• .750″ gas block journal
• M4A1 diameter for reduced POI shift / Increased Accuracy & Durability
• Air gauged and hand lapped bore
• Polished chamber and M4 feed ramps
• TRU-BORE™ suppressor quality threads
• Suppressor optimized gas ports
• .625″ , 1/2×28 industry standard threads

Griffin Low-Pro rails are a slim, low profile, ultralight, yet rigid M-LOK rail. Design objectives of this rail were to provide a slim, ultralight rail, with increased rigidity over similar weight and profile current market options. A custom extrusion provides significant internal reinforcement to reduce flex when gripping the carbine firmly in the shoulder pocket. Understanding the importance of low light targeting, these reinforcements provide rigid mounting for IR laser aimers ensuring minimal POI shift when torque is applied to fore-grip type accessories, or when loads are applied to the rail (shooting off barricades, loaded bipods etc). Internal testing showed 70% less POI shift with laser aimers versus competing “slim rails”. Carefully positioned slots in the rail allow for rapid cooling when running the carbine fast while maintaining rigidity.

The Low-Pro rail features a lightweight 7075 T6 Aluminum barrel nut, which can be installed with any car stock wrench or by using the included Griffin Armorers Wrench. Included shims allow barrel nut timing and keep the rear section of the rail low profile and ergonomically pleasing for relaxed posture carry at static positions. The included 17-4 stainless steel anti rotation QD sling swivel sockets install through the rail using a standard QD sling swivel (not included) and into the nut, ensuring that the rail is kept as low-profile as possible. In the same way, flat socket head cap screws are used in keeping with the sleek design objectives.

M-LOK slots at the 3, 6, and 9 o’clock positions allow for mounting of your favorite M-LOK accessories.

• Length: 10.5″
• Height 2″
• Internal Diameter 1.35″ (measured from inside of reinforcement spars)
• Width: 1.54″
• Weight: 7.4 ounces
• Weight Installed: 9.32 ounces

Rail Kit video is posted below. To receive included items in this video see our rail Kits.

The PRIMO™ Gas Block is a low profile billet machined, .750″

ID block, made from nitrided 416R crucible alloy steel.

The block has two provisions for mounting, set screws and / or pinning. The included splined pin allows qualified gunsmiths and experienced builders the option of having a military style secured gas block. A 1/8″ carbide drill bit and three ton press are recommended for pinning. Knurl grip cup pointed fasteners ensure a secure attachment to host barrel. The PRIMO’s pre-drilled hole helps locate the drilling operation on pre-dimpled barrels for fixture free installation.

Features

• 416R Crucible Alloy Steel
• QPQ Nitride finish
• .750″ gas block diameter compatible
• low profile design
• included splined pin
• Knurl grip – cup pointed fasteners
• included hex key
• Included gas tube roll pin
• Pre-drilled for ease of barrel pin installation

The SN-ACH™ (Suppressor Normalized Ambidextrous Charging Handle) is a patent pending modernized, feature filled charging handle that will satisfy any AR15 user. The SN-ACH™ features a gas check groove and a suppressor gas vent that reduces gas in the face of the shooter when using a suppressor. Configurable levers were also added so that a user could choose to run the included large lever, which works with gloved hands, or purchase and modularly use the smaller levers (available separately) without having to buy an entirely new handle at a excessive cost. The bolt carrier engaging hook features durable reinforced geometry for 30% increase in strength over milspec handles and approximately 3 times as strong as inferior 6061 handles which routinely break under hard use. Fitment bearing surfaces on the handle mating ensures reduced wobble fitment with the Ar15 and AR10 upper reciever. The handle is made from 7075-T6 aluminum and hard coated for optimal wear resistance- the Griffin SN-ACH is the finest charging handle available for the AR series family of firearms.

The Griffin Armament Rail-Shield™ 4 piece M-LOK Compatible furniture kit is the first serious hard use furniture set to reach the market. Unlike other systems relying on plasticsnap on attachment, the Rail-Shield™ furniture kit uses grade 5 fasteners for solid attachment. Rail shield panels protect the shooters support hand from direct exposure to hot rails, as well as insulate during handling in extreme cold weather. The optional handstop bottom panel provides ergonomic enhancement and recoil control. Texturized surfaces do not drag on gear, or cause discomfort but promote positive control of the firearm.

 Includes mounting hardware, 2 contour side panels, 1 handstop bottom panel, and one alternate flat bottom panel. Mounted weight is 2.4 ounces, total weight with the optional flat panel and handstop (one of which is mounted in the used configuration) is 3.1 ounces

Four color options are available to match your other Griffin Armament furniture.

M-LOK™ is a trademark of Magpul Industries Corp.

Features

• Grade 5 mounting hardware
• 4 colors available
• 2 mounting configuration options

Why a BCG from Griffin Armament? The simple answer is that these BCG’s are the best we’ve used in our ten years of military service and over a decade of industry involvement. When you look at a top shelf product you can see its quality. These are the best mil spec pattern there are.

The Griffin BCG combines an 8620 carrier, 9310 Bolt, 4340 cam pin and extractor. All the proper heat treats, the correct shot peen, and the often neglected post heat treated grind are present. In a market filled with cast component BCG’s, all components are billet machined and all surfaces receive a finish pass in machining for improved surface smoothness. There are varying degrees of quality in Melonite QPQ finishes. These BCG’s went to 4 finishing houses for selection of the finish provider, cost not being a consideration. The result is a deep black finish with remarkable lubricity. These are assembled to the current military technical data package with permatex’d and properly staked carrier keys. They also feature the current 15,000 round extractor spring design and a Crane O ring for reliable extraction in extreme conditions. We ran these thousands of rounds in multiple manufacturers rifles throughout the T&E phase without a single malfunction. From first sight through months of use to the final product launch we have remained excited to bring this BCG to market. This is the only BCG that has ever excited us and that is why we have chosen to offer it to the people we care about, our customers.

Many Metallurgists consider AISI 9310 alloy steel as an acceptable bolt material and substitute for Carpenter 158 (Carpenters brand name AISI P6 Spec mold steel). However, for the M4 purists we offer our BCG with the optional Carpenter 158 bolt made to current Mil-Spec including phosphate rather than Melonite treatment which comes with the 9310 bolt.

Features:

• 8620 Carrier
• 9310 Bolt MP inspected, High Pressure Tested (Carpenter 158 available)
• Bolt properly heat treated, shot peened, and post heat treat ground with headspace held to half the blueprint specification
• 4340 Cam Pin & Extractor
• Finish Pass Machined on all surfaces
• Full Billet Construction
• Premium Melonite QPQ Finish
• Latest 15k round Extractor Spring Design
• Crane O-ring for increased extraction reliability in extreme conditions
• Billet machined gas key, installed with permatex and staked to current TDP

Griffin Armament is proud to introduce affordable Micro Modular Sights (M2) compatible with Picatinny rail systems. Griffin M2 sights offer an industry first, patent pending, modular base plate system. Constructed from QPQ Treated 17-4 and ordnance grade steel, Griffin M2 Sights were designed to be the correct product for every backup sight application.

A shooter can use these durable, low profile sights in a 12 o’clock mounted application while having the flexibility to reconfigure them to ambidextrous 45 degree angle sights using the alternate and available angle plates. This flexibility ensures these sights can be used by anyone and will never end up in a box of undesirable legacy kit. The full M2 deployment kit includes the front and rear sight assemblies as well as both vertical and angled bases for a complete modular system. However, sights and bases are available separately for users who wish to buy parts as needed. The front A2 sight provides elevation adjustment while ensuring maximum aftermarket support for your favorite post, be it tritium, fiber optic, match grade, or otherwise. An extremely low profile, snag resistant, slotted rear windage screw, affords easy but more importantly secure adjustability.

Robust spring tension of both front and rear flip up assemblies ensures accurate repeatability every time the sight towers are actuated.

Never before has a product in this category offer this degree of flexibility. Griffin M2 Sights have a minimal foot print, and are among the smallest backup sights on the market. For a mere 2 and half ounces your rifle can be equipped with a durable iron sight system, to provide aiming capability in rain, snow, or fog, on or off axis without dependence on batteries or glass.

Features

• • 17-4 stainless steel
  • Melonite QPQ treated
  • Angle plates and 12 o’clock plates included
  • Fasteners included
  • A2 sight post compatible

Standard and Optional Features of the MK1 Uppers:
Griffin 416R SS HEDP™ Barrels
Griffin Enhanced BCG
Griffin Forged Upper with Type 3 hardcoat anodized
Griffin SN-ACH™ (Suppressor Normalized Ambi Charging Handle)
Griffin Contour Connect QD End plate
Griffin RailShield™ 4 piece panel set
Griffin Low Pro rail system
Griffin Micro Modular Sights™ 
Griffin Primo Gas Block (pinned)
Griffin Silencer Mount Muzzle Device

MK1 Uppers do not come pinned and welded.