MK1 PSD Pin & Weld One-Stamp 9.5" 300BLK (w/ GP7)

Now: $2,390.00
(You save )
(No reviews yet) Write a Review

Out of stock






Billet machined from 2 pieces of 17-4 Stainless steel, this device is precision TIG welded together to provide the largest possible internal expansion chamber in a Taper Mount. This design would be impossible to manufacture in a single CNC cut work piece.  The welded on front cap features gas jet nozzles protected by a wire cutter shroud to focus concussive blast forward and away from the shooter and bystanders in the immediate vicinity. CNC machining this device in two pieces is more expensive and time consuming than a single piece device for both machine time and human handling however no corners were cut to produce the optimal design.   For users seeking the lowest concussion muzzle device that can be used either stand alone or with a suppressor this is the unit for them.  

Taper Mount Thread Protector is compatible with this muzzle device for added protection of thread mounts.


  • Rock Solid Lock up
  • Free of wear prone geometry
  • Front cap shields blast and funnels it forward
  • Precisely calculated porting to encourage flow forward of the muzzle
  • Large internal expansion chamber to reduce concussion
  • Precision TIG welded assembly
  • Sacrificial baffle strategically engineered to extend the life of your suppressor
  • 17-4 PH Stainless steel to withstand hard use
  • Lustrous Melonite Finish
  • Griffin Laser Logo Marked
  • Shim set Included
  • Pre drilled 3mm hole for pinning and welding


  • Diameter: 1.075" (taper), 0.93" unit
  • OAL: 2.27"
  • Weight: 2.5 oz.
  • Material: 17-4 H900 Stainless Steel
  • Finish: QPQ Black Nitride
  • Thread Pitch: 5/8x24 .30 cal

HEDP™ Barrel

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.


  • 416R SS barrel manufactured from stress relieved certified barrel steel
  • Black nitrided for extended service life
  • Magnetic particle inspected
  • Button rifled
  • 300 BLK chamber
  • Pistol length gas
  • .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" , 1/2x28 industry standard threads


  • Length: 11.5"
  • Weight: 24 oz.

PRIMO Gas Block

The PRIMO Gas Block is a low profile billet machined, .750 ID block, made from nitrided 416R crucible alloy steel. Knurl grip cup pointed fasteners ensure a secure attachment to host barrel. 


  • 416R Crucible Alloy Steel
  • QPQ Nitride finish
  • .750" gas block diameter compatible
  • low profile design


  • Weight: 1.5 oz

SR Rail

Griffin Armament® M-LOK compatible SR rails (Suppressor Ready) allow up to 1.5” outside diameter silencers to be mounted inside the octagonal M-LOK rail. This provides suppressor aficionados a sleek, and compact overall length to AR15 type firearms.

Design objectives of this rail were to provide a suppressor compatible rail, with increased rigidity and durability over similar weight and profile current market options. A custom extrusion provides significant internal reinforcements to reduce flex when loading the carbine on the rail. 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 such as practical shooting off barricades or when loading bipods for rapid follow up shots. Internal practical testing showed substantial reductions in POI shift with laser aimers versus competing "slim rails" that lacked this notable product feature.

The new SR rails features a close tolerance, heavy-duty, 7075 aluminum, T-6, type 3 hard coat anodized finish. The barrel nut can be easily installed to 35-85 ft/lbs using the included Griffin Armorers Wrench.  The new slip fit clamp design is extremely user friendly and does not require any shims or special timing methods. The clamp geometry in the rear section of the rail is low profile and ergonomically pleasing even for long durations of extended carry at static security positions. Flat head T15 torx screws should be tightened to 25/in pounds. The included 45 degree picatinny QD sling swivel can be installed on the top picatinny rail to the desired position of the end user.  M-LOK flats on each 45 degree surface allow for mounting of your favorite M-LOK accessories. A contiguous picatinny top rail ensures repeatable and accurate mounting for night vision and thermal systems. 


  • 7 sides of M-LOK interfaces
  • Contiguous 1913 Picatinny top rail
  • Low profile, user friendly, clamp installation design
  • 6061-T6, Type 3 hardcoat anodized SR Rail
  • 7075, T-6, Type 3 hardcoat anodized, aluminum barrel nut


  • Length: 12.5"
  • Height 2"
  • Internal Diameter 1.54" (measured from inside of reinforcement spars)
  • Width: 1.54"
  • Weight Installed: 11.9 ounces

Rail Shield™ kit 

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 plastic snap 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


  • Grade 5 mounting hardware
  • 4 colors available (Black, Grey, FDE, & OD Green)
  • 2 mounting configuration options


  • Mounted Weight: 2.4 oz. 
  • Total Weight: 3.1 oz. (with optional flat panel and handstop)

Enhanced BCG

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.


  • 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


The SN-ACH™ (Suppressor Normalized Ambidextrous Charging Handle) is a patented, 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. The bolt carrier engaging hook features durable reinforced geometry for 30% increase in strength over milspec handles and approximately 3x 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 upper reciever. The handle is made from 7075-T6 aluminum and hard coated for optimal wear resistance.


  • 6061-T6, Type 3 hardcoat anodized 
  • Fits all standard AR15/M4/M16 family firearms

AR-SOB (Suppressor Optimized Buffer)

The AR suppressor optimized buffer is a spring loaded, staggered impact, urethane buffered design. The reciprocal and non-reciprocal weights are similar to the A2 rifle length buffer. In conjunction with shock dampening brass weights, the AR-SOB offers increased system dwell time, reduced bolt speed, and enhanced chambering reliability. Through integration of a shorter platter of CNC machined weights and a telescoping buffer head, the AR-SOB has more controlled motion tolerances, allowing precisely controlled timing and forced sequential impact of buffer weights interacting with the rifles operating system. The AR-SOB weighs 4.9 ounces, and can be used in suppressed 5.56mm rifles as a replacement for the M4 carbine series buffers, and also in 308 carbines as a replacement for H2 and H3 buffers when used in conjunction with the AR10 mil-spec CAR receiver extension and AR10 CAR action spring.


  • Brass weights and heat treated 17-4 Stainless Steel construction
  • Staggered impact hybrid buffer design
  • Rifle buffer function in a CAR system size for unsurpassed reliability
  • Ar10 Car compatible when used with AR10 Car receiver extension and spring


  • Weight: 4.9 oz

Maritime Receiver Extension

A six position, mil-spec dimensioned receiver extension featuring 7 ports to allow excess gas, water, oil, and debris to leave the operating system, reducing pressure and associated danger to both host firearm and shooter, while enhancing reliability. Mil-spec hardcoat anodized. 7075-T6 is twice as strong as 6061-T6.


  • 7075-T6 Aluminum
  • Mil-spec hardcoat anodized
  • 6 positions
  • 7 ports to enhance clearing of operating system

Contour Connect QD Endplate

For users seeking a sleek, refined, anti-rotation QD end plate, the C2E Contour Connect End Plate is the perfect compliment to any AR15 or AR10 pattern rifle. Perfect for single point slings, where rapid strong to weakside transitions and rapid primary to secondary firearm transitions are desired.

Made from heat treated ordnance grade steel, and manganese phosphate finished for extreme durability. with a machined 8 position anti-rotation QD sling mount socket, the C2E follows the contours of the forged Mil-Spec lower perfectly, giving the lower receiver end plate a forged feel. A 45 degree chamfer with smooth corner radii gives the C2E a premium feel your rifle always should have had.


  • Heat treated ordnance grade steel
  • Mil-Spec Manganese Phosphate finish
  • 8 position Anti-Rotation QD Socket
  • Smooth contour matching geometry for Mil-Spec forged lower receivers
  • Minimalist value added firearm enhancement


  • Weight: 0.5 oz.

Enhanced Trigger Guard

The Griffin Enhanced Trigger Guard offers a more comfortable guard than mil spec, while filling in the rear void in the receiver trigger guard boss that commonly irritates the middle finger.

A bit more room accommodates lightweight gloves better than the milspec. A spartan upgrade to the Ar15 but none the less a quality part.

90 Degree Ambi-Selector

Built around a heat treated ordnance grade steel central selector hub, two black nitride 17-4 selector paddles can be configured to the users needs whether the user is right or left handed. The hub incorporates an optional screw for trigger match style overtravel adjustment of standard AR-15 or M4/M-16 triggers, enhancing the human interfaced accuracy of the host firearm (enhanced shoot-ability).  Overtravel adjustment reduces the time that the applied trigger pull weight is removed from the rifle during firing after the trigger break and prior to reaching the limit of travel.  Reducing this time of lost equilibrium, reduces the wobble zone created by the removal of weight at the moment of break.  

Utilizing the traditional 90 degree pattern, this selector requires the manipulation you are familiar with and have come to expect in the AR-15 / AR10 family of firearms.


  • heat treated 17-4 ordnance grade steel selector paddles and central selector hub
  • Black nitrided paddles
  • Paddles can be reconfigured for left or right handed users
  • Paddles match the stylistic geometry of the Griffin Armament Suppressor Normalized Ambidextrous Configurable Handle (SN-ACH™)

Dimpled Takedown Pins

Typical production AR-15 pins are ~.245" diameter and flat on the ends. They operate in .250 pin holes, and items used to push the pins occasionally slide off and can scratch your lower receiver.

This pin set is ~.248" diameter, allowing you to improve your upper to lower receiver fit, and features early Armalite / early Colt style dimples to assist in location of bullet tips or tools used to push the pins. The tool locating dimples reduce the likelihood of scratching your lower and add a nice feature to ease dis-assembly.

A3 Grip

The A3 provides excellent comfort and ergonomic feel, without loss of positive weapon retention or ease of safety selector manipulation. The Griffin A3 is compatible with the USGI trigger guard's winter guard function for gloved or mitten use. Textured to match the Griffin Armament Rail-Shield M-Lok furniture kit.


  • Comfortable & Ergonomic feel
  • Textured to match ourRail Shield™ 4 piece M-LOK furniture kit

Extreme Condition Stock

Manufactured from high strength materials, the Griffin ECS™ is a compact, fully featured, no-compromise stock you can count on.

The ECS™ confronts design deficiencies in legacy systems. The current issued locking latch pin will bend and shear at the reduced diameter threaded shank, promoting stock failure- Griffin replaced it with a full diameter hardened stainless steel tool pin. The music wire spring is not a material recommended for outdoor use- the Griffin ECS™ uses 17-7 stainless steel springs which are outdoor use rated. The Griffin ECS™ also has water and debris evacuation ports compatible with the Griffin Maritime Receiver Extension, increasing system reliability and durability in extreme conditions. An anatomically angled, 60A Shore durometer rubber pad promotes straight line recoil, reducing muzzle climb associated with 90 degree angled systems. The rubber pad further provides non slip shouldering and comfortable recoil dampening, in weather conditions to -40F. An Ambidextrous, anti-rotation QD sling point is integrated into the stock, eliminating the capacity of the sling to wrap up when the firearm is stored or handled un-slung.


  • 17-7 stainless steel spring
  • Evacuation ports for water & debris, compatible with the Griffin Maritime Receiver Extension
  • Anatomically angled, 60A Shore durometer rubber pad promoting straight line recoil
  • Non-slip shouldering & comfortable recoil dampening
  • Ambidextrous, anti-rotation QD sling point integrated into the stock


  • Weight: 8.5 oz. 


Choice of furniture color

Options Available:

Additional Details

Barrel Length (inches):
223 Wylde

Related Products

Customers Also Viewed