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AR-15 SUPER DUTY RIFLE BUILD KIT 5.56MM

AR-15 SUPER DUTY RIFLE BUILD KIT 5.56MM Reviews & Ratings

The Geissele Super Duty Build kit features the quality and workmanship you've come to expect from the Geissele name.

The complete upper, chambered in 5.56mm, features a nanoweapon-coated HUXWRX Flash Hider QD muzzle device mounted to an in-house durable manganese phosphate coated, Cold Hammer Forged, Chrome Lined, 1-7 twist Geissele barrel. Geissele barrels are precision machined, utilizing the highest quality materials at their state of the art facility in North Wales, PA. The Geissele Length gas system and Geissele Super Compact Gas Block (with bomb-proof installation) ensures reliability and optimal performance in extreme conditions and heavy use.

The included MK16 Super Modular rail mates with the upper receiver via a center aligning tab, removing any chance of rail rotation. This MK16 rail is a variant of the SMR MK16 currently fielded by USASOC and renowned by operators for their performance, comfort, and adaptability.

At the heart of this upper receiver group is the Geissele REBCG (Reliability Enhanced Bolt Carrier Group). This Nanoweapon coated BCG features a properly torqued and staked, chrome lined gas key. The Cam Pin is machined from advanced tool-steel, which is also coated with Nanoweapon for maximum corrosion and wear resistance. The REBCG features extended upper rails, providing greater stability and dramatically increasing feeding reliability. Additionally, the REBCG comes with the Geissele Stressproof Bolt, which is manufactured from Carpenter 158+ steel. Directly developed with Carpenter Steel metallurgists to create a material that is cleaner and has less impurities, the Stressproof bolt is stronger and more fatigue-resistant than you average bolt. The Geissele Stressproof bolt is also forged, not machined from barstock. This optimizes the grain structure of the steel to yield a bolt capable of five times the lifespan of a mil-spec bolt. Each bolt is rigorously inspected, high-pressure tested, mag particle inspected, and Nanoweapon coated.

The Geissele Ultra Duty Lower Parts Kit is made for the most demanding operators and includes all the internal parts necessary to complete or rebuild your lower receiver. This top-tier LPK features proprietary Geissele designs, machined with great care at their facility located in North Wales, PA. Key components are made from Stainless Steel, which offers a much longer life-span and a much lower chance of rusting or failing in extreme conditions or under heavy use. It includes the Maritime Bolt Catch, famous for its aggressive texturing and extended paddles, and the Ambidextrous Super Configurable Safety, which features the ability to easily and securely swap and exchange the safety levers, plus provides the end user a satisfying and positive tactile feedback when the safe or fire position is engaged. The takedown pins and mag release button feature the same “tank treading” as the Maritime Bolt Catch, giving your rifle a tasteful and cohesive look. Included in the Ultra Duty LPK is Geissele’s Ultra Precision Trigger Guard. It is 5-axis machined out of a solid block of billet 7075-T6 aluminum and Type-3 hardcoat anodize to ensure that your build stands apart from any other. Each of these components are constructed with an eye toward improving the usability of the AR platform by allowing for more tactile engagement and easier access to critical control components.

Normally exclusive to Super Duty firearms is the SSA-E X with Lightning Bow® trigger. This nanocoated, two-stage trigger features a wide body and bow shape that finds the perfect balance between a classic M4 trigger and a flat body trigger. The SSA-E X’s light and clean first and second stage pull weights result in a trigger with a smooth, light first stage take-up, and an ultra-crisp second stage break.

The Geissele Premium Mil-Spec Buffer Tube is machined from quality 7075-T6 Aluminum and finished in Type 3 Hardcoat Anodize. This rigid and durable buffer tube conforms to all mil-spec standards and features six pre-set stock positions. This carbine-length, mil-spec diameter Premium Buffer Tube is the perfect fit for your AR-15 lower. Included is a high quality, Mil-Spec castle nut and end plate.

The Geissele Super 42 Buffer Spring and Buffer Combo was designed to improve the function and reliability of the AR-15 pattern rifle. Its unique spring design uses three independent strands of wire, just like the famous German MG42 Machine Gun. This concept acts as a harmonic dampener and energy absorber by allowing the strands to flex separately from each other. This flex helps displace excess energy, which decreases the chance of spring failure and assists with making your AR-15 more reliable.

Compared to the stock spring, the Geissele Super 42 Spring has a decreased tendency to lose length and force over a given round count. As an added bonus, it removes the annoying spring reverberations (the “twang”) heard and felt by the shooter through the buttstock. The Super 42 Spring has a 15% stronger average return force than the standard buffer spring. This will assist in stripping rounds out of the magazine when operating with a dirty weapon or when using steel-case ammo.


Currently employed by the U.S. military, the B5 stock is a reinforced polymer stock that fits AR-15/M4-type receiver extensions and offers an improved cheek weld, designed for increased comfort and consistency. Two waterproof storage compartments running the length of the stock hold 2 AA or 3 CR-123 batteries. Streamlined contours resist snagging on clothing, equipment, or vegetation to aid in safe and stealthy operation. A Sure-Grip stock latch ensures convenient and intuitive length-of-pull adjustment, while the anti-slip rubber recoil pad secures the weapon to the operator’s shoulder. It features a stainless-steel QD swivel mount and two molded 1¼" wide sling slots.

The Geissele A22 Grip is a modern take on the classic 1911 grip angle for the AR15/M4 platform. Incorporating a similar angle as the well-known 1911, the Geissele A22 Grip also features attractive anti-slip texturing and a thicker palm swell to assist with easily attaining a high tight hold.





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5 Stars
82%
4 Stars
18%
3 Stars
0%
2 Stars
0%
1 Stars
0%
Reviews Summary
Overall, customers are impressed with the craftsmanship and quality of the AR-15 Rifle Build Kit, praising its ease of assembly and superb performance. While most reviews are positive, a few customers reported missing parts but noted that customer support addressed their concerns effectively. Many recommend this kit for high-end AR builds at a reasonable price.
What Reviewers Are Saying
Product Quality
75%
Reviewers consistently highlight the exceptional quality and craftsmanship of the kit, noting that every part reflects high-end manufacturing standards. This theme resonates strongly, ensuring customers feel they are investing in a well-made product.
Ease of Assembly
60%
Many users appreciate how simple the assembly process is, often taking around 30 minutes, which contributes to a positive overall experience. This ease is particularly appealing to those new to building rifles.
Customer Service
30%
Some reviews mention missing parts, but customers appreciate the responsive customer service that effectively resolves these issues. This indicates a commitment to customer satisfaction, enhancing the brand's reputation.
Value for Money
50%
Several customers emphasize that the kit offers high-end features at a competitive price, making it an attractive choice for those wanting quality without overspending. This adds to the overall appeal of the product.
Performance
40%
Users report excellent shooting performance and accuracy after assembling the kit, enhancing customer satisfaction. Many describe their builds as 'tack drivers,' proving this kit delivers on its promises.
5
Geissele Rifle Build
Good quality and cheaper then buying separately especially when on sale.
Would you recommend this? Yes, I would recommend to a friend
5
The hype is real
Everything is better than expected.
5
Geissele Super Duty Kit
Amazing Craftsmanship and Product… Highly Recommend…Brownells was Great as Always to Purchase through… Fast Shipping arrived in Perfect Condition… Thank You Brownells for another Great Transaction…
Would you recommend this? Yes, I would recommend to a friend
5
Super Duty Super Awesome
Every thing you need except a stripped lower receiver of choice. Took about 30 min to assemble. Can’t beat this deal.
Would you recommend this? Yes, I would recommend to a friend
5
Amazing Craftsmanship
This is now, the nicest rifle I own, and the quality and craftsmanship of virtually every part in this kit is just superior to anything I’ve had or used before. Geissele is well known for high-end manufacturing, and you can see that level of care and detail in every part. I wish my service rifle had been this nice. I was so impressed, I bought a second for the wife. Can’t recommend it enough.
Would you recommend this? Yes, I would recommend to a friend
5
Super nice and accurate
I am really happy with my purchase, the support and helpfulness of Brownells.
Would you recommend this? Yes, I would recommend to a friend
5
Great, simple, high end
If you’ve ever wanted a high end AR15 but wanted to save a little money, this kit is the way to go. Just get yourself a good lower(I went with a Griffin stripped ambidextrous lower) and you are off to the races. Fun is accurate and topped with my PA PLX-C 1-8, it’s a tack driver. Only downside is the fact that I’m tempted to pull the trigger on a Huxwrx can now.
5
Super Duty Build Kit
Fit, finish and quality are excellent! I put it on a Geissele Super Duty lower receiver I picked up on a blemula sale. This is my second Geissele build the other is 14.5 URGI. The grouping is tight and consistent with both, ammo I used to test grouping and zeroing was "Lake City by Winchester 5.56 NATO M193". I have not had any issues running hornandy, winchester, nosler , black hills ammunition, or Winchester white box. PMAGS, USGI Mags, those hybrid Mags that are steel and polymer LMW or something all work great.
5
Absolutely Amazing Rifle!
I put this kit together in the thunder ranch aero precision lower and it went together easy and shoots amazing. The trigger is exactly what you would expect from geissele and as far as I can tell everything else is amazing too
4
Missing Parts
My kit was missing the castle nut, the receiver end plat, and an installation pin that should have been in the trigger package. It looked like the trigger bag had been opened already.