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  • Post category:AR-15 / Lower Receivers
  • Post last modified:April 6, 2024
  • Post published:December 8, 2022

Best Lower Parts Kit AR15 Review

What is an AR-15 Lower Parts Kit? 😏

It is a package of components needed to build the lower receiver of an AR-15 rifle. This kit typically includes all the necessary parts such as the trigger, hammer, disconnector, selector, bolt catch, magazine catch, and the springs, pins, and detents that hold everything together. It’s a crucial component for firearm enthusiasts who wish to custom-build their AR-15, allowing for personalization and the opportunity to understand the mechanics of their firearm more intimately.

Our Top Pick
CMMG Lower Parts AR15 Gun Builder’s Kit
The CMMG Lower Parts AR15 Gun Builder’s Kit is an ideal choice for individuals interested in assembling their own AR15-style firearm. This comprehensive kit incorporates a wide range of essential components, such as the bolt catch, pivot pin detent, selector, and more. By providing all these necessary parts in a single package, this Lower Parts Kit offers a cost-effective solution, eliminating the need to purchase each item individually.
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Features 🧐

🔘 They are highly sought-after by firearm enthusiasts due to their exceptional features and advantages. These kits offer a remarkable level of scalability, allowing users to choose between basic and premium versions based on their specific requirements and budget. ➡️ This ensures that every individual can find a kit that perfectly aligns with their needs.

🔘 Moreover, these kits provide unparalleled comprehensiveness, as they include every tiny part required for the lower receiver. ➡️ This eliminates the hassle of sourcing individual components and guarantees that users have everything they need in one convenient package.

🔘 Furthermore, these kits are renowned for their exceptional quality and durability. They are meticulously crafted using high-quality materials, ensuring that each part is capable of withstanding high levels of stress and usage. ➡️ This ensures that firearm enthusiasts can rely on their AR-15 even in the most demanding situations, providing them with the utmost confidence and peace of mind.

🔘 In addition to their reliability, some Kits also offer improved ergonomics for triggers and selectors. ➡️ This enhances user comfort and control, making the shooting experience even more enjoyable and precise.

🔘 Last but not least, these kits cater to the customization needs of users, allowing firearm enthusiasts to personalize their AR-15 according to their preferences. ➡️ This not only enhances the functionality of the firearm but also adds a unique and personal touch.

Our Top Pick
Sharps Bros – Ar-15 Lower Parts Kit With No Fire Control
This comprehensive set comprises entirely of components made in the USA, meticulously crafted to meet our stringent standards. By eliminating overseas production and the fire control group, we guarantee top-tier quality at an affordable price. This kit is designed for a variety of essential parts, including the bolt catch, selector detent, magazine catch assembly pins, takedown pin, pivot pin detents, buffer retainers, and a complete spring kit.
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Benefits 🤠

➡️ Firstly, a lower parts kit contains every small component needed to assemble the lower receiver of an AR-15. This includes the all-important trigger group, safety selector, magazine release, bolt catch assembly, pins, springs, and detents. The comprehensiveness of a kit prevents any missing parts that could stall a rifle build.

➡️ Secondly, purchasing a purpose-built lower parts kit allows all the included components to properly interface and work in harmony right out of the box. Reputable brands design their kits for a flawless fit and seamless interaction between parts like the trigger, hammer, safety, and other controls. This results in smooth overall operation.

➡️ Moreover, the convenience of buying a pre-packaged kit means not having to source each individual small part separately. This saves time and hassle trying to track down springs, detents, etc. one by one.

➡️ In addition, these kits provide an opportunity to customize and upgrade rifle controls to your preferences. Swapping out basic parts like the pistol grip, trigger, and ambidextrous selectors allows tailoring the rifle to your shooting needs.

➡️ Finally, reputable brands engineer their lower parts kits from durable alloys and coatings built to withstand rugged use. The longevity these kits provide results in a rifle that can be handed down for generations when proper care is taken.

Maintenance 😎

Maintaining and cleaning your Lower Parts Kit is essential for ensuring the performance and longevity of your firearm. Follow these steps for effective cleaning and maintenance:

  1. 🟢 Disassembly: Begin by disassembling your AR-15. Make sure the gun is unloaded and then remove the lower receiver, being careful not to lose any small parts.
  2. 🟢 Cleaning: Clean each part individually. Use a quality gun-cleaning solution and a small brush to scrub each component. Pay special attention to the trigger, hammer, and selector, as these parts often collect the most debris.
  3. 🟢 Inspection: After cleaning, inspect each part for signs of wear or damage. This includes checking springs for tension, inspecting pins for any bends or cracks, and examining the trigger and hammer for any signs of excessive wear.
  4. 🟢 Lubrication: Proper lubrication is critical to ensuring smooth operation. Apply a thin layer of high-quality gun lubricant to all moving parts, focusing on the trigger, hammer, and other controls.
  5. 🟢 Reassembly: Carefully reassemble your AR-15, ensuring all parts are securely in place. Test the function of all controls to confirm everything is working as expected.
  6. 🟢 Storage: Store your firearm in a clean, dry place to prevent rust and corrosion. If your firearm is not being used regularly, consider using a rust preventative on metal parts.

Follow these steps regularly to keep your kit in optimal condition and ensure your firearm performs flawlessly when you need it most.

Watch this video to find more information 💻

Best Lower Parts Kit AR15 Review

1# Geissele Standard Lower Parts Kit

Geissele Standard Lower Parts Kit

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For those who are serious about their AR15s, the Geissele Standard Lower Parts Kit No Grip is a must-have for any firearm enthusiast. This Mil-Spec kit from Geissele contains 18 essential components necessary to complete or rebuild your lower receiver—everything you need minus the grip. Among the included parts is their Posi-Lock safety system, which provides positive tactile feedback when shifting between safe and fire positions so that you can confidently trust what mode your gun is currently in.

Thanks to this durable design, this Geissele 05-343 Standard Lower Parts Kit will help ensure your lower receiver performs at its highest potential. Don’t settle for anything less than excellence; get top-quality results with the trusted Geissele Standard Lower Parts Kit without a grip package today.

  • 18 essential components
  • Posi-Lock safety system
  • Durable design
  • Does not include a grip
  • Some users report issues with a safety system


2# CMMG AR-15 Lower Receiver Parts Kit

CMMG AR-15 Lower Receiver Parts Kit

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Assembling an AR-15 lower receiver doesn’t have to be complicated. With the CMMG AR-15 Lower Receiver Parts Kit, you can easily and efficiently complete the part of your gun build. This kit contains all the parts necessary to make a fully functioning lower receiver for your build. Parts are broken up into colour-coded bags, so finding and organizing components is a breeze. From springs and pins to other required parts – this kit has them all!

Video review

  • Colour-coded bags make finding and organizing components easy
  • All the parts necessary to make a fully functioning lower receiver are included
  • Fast and efficient assembly
  • Not all components are necessary
  • May require some additional assembly


3# CMMG Lower Parts AR15 Gun Builder’s Kit

CMMG Lower Parts AR15 Gun Builder's Kit

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The CMMG Lower Parts AR15 Gun Builder’s Kit is perfect for those looking to build their own AR15-style firearm. This kit includes most of the components you need, including bolt catch, pivot pin detent, selector, and more. With everything you need in a single package, the Lower Parts Kit is an economical way to get all the small parts you need without having to buy them individually. And with a manufacturer model of 55CA601, you can rest assured that these are true mil-spec parts, so your completed AR won’t just look good – it’ll function safely and reliably.

  • All components are mil-spec
  • Economical way to get all the small parts you need
  • Includes bolt catch, pivot pin detent, selector, and more
  • May not include all components you need


4# CMMG AR-15 Lower Receiver Pins and Springs Parts Kit

CMMG AR-15 Lower Receiver Pins and Springs Parts Kit

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Are you looking for the best-guaranteed way to keep your AR-15 rifle in top-quality condition? The CMMG® AR-15 Lower Receiver Pins and Springs Parts Kit will ensure that your AR-15 rifle consistently operates at peak performance levels, with all parts meeting or exceeding mil-spec standards.

Replacing standard parts often found on AR-15 rifles with this kit, you can be sure of a seamless installation and reliability when it comes to performance. The model number is 55AFF75, so next time you head out to the shooting range make sure your weapon is as good as new by replacing those necessary standard parts with this kit from CMMG®.

  • Keeps your AR-15 rifle in top condition
  • All parts meet or exceed mil-spec standards
  • Reliability
  • Installation may be difficult for some


5# Smith & Wesson M&P AR-15 Lower Parts Kit

Smith & Wesson M&P AR-15 Lower Parts Kit

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If you need mil-spec parts to build and customize lower receivers, then look no further than the Smith & Wesson M&P AR-15 Lower Parts Kit. This updated kit includes all of the essential parts, including bolt catches, buffers, disconnectors, hammers and pins, magazine catches, pistol grips and screws, selector detents and springs, take-down pins and springs, trigger guards roll pins and triggers. High-quality craftsmanship goes into every part to ensure your accuracy while the building is precise and consistent.

Made in the USA with superior materials such as steel alloys and heat-treated metals you can rest assured that your M&P AR-15 will last for years. For enhanced customization options, this parts kit is just what you need to ensure your receivers are exactly how you want them.

Video review

  • Made in the USA with superior materials
  • Enhanced customization options
  • Precise and consistent building
  • Some parts may not be compatible with other brands
  • Instructions are not included


6# Aero Precision AR15 Lower Parts Kit

Aero Precision AR15 Lower Parts Kit

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Are you ready to build the premium AR of your dreams? The Aero Precision AR15 Lower Parts Kit is exactly what you need. This kit includes 17 gun parts that will help you finish your custom AR15 build and provide you with optimal quality. Plus, these parts are Mil-Spec dimensions and coatings, making them engineered and designed to maximum excellence. Your dream gun needs the best parts!

Get the Aero Precision AR 15 Lower Parts kit today and make sure you have everything you need for a top-notch custom rifle. With components like a bolt catch, safety selector, takedown pin and magazine catch included in this kit, a high-quality weapon can easily become your reality.

Video review

  • Mil-Spec dimensions and coatings
  • Engineered and designed to maximum excellence
  • Bolt catch
  • Safety selector
  • Takedown pin
  • Magazine catch
  • Parts may not be coated to your liking
  • Safety selector switch may be difficult to install


7# Aero Precision AR15 Standard Lower Parts Kit

Aero Precision AR15 Standard Lower Parts Kit

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The Aero Precision AR15 Standard Lower Parts Kit is the perfect choice when it comes to putting together the lower of your custom AR15 build. Our parts are all manufactured to mil-spec dimensions and coated for quality assurance, so you can be confident that you’re getting the best possible interface between components. Plus, with our Enhanced Lower Parts Kit offering an upgraded Magpul MOE Grip and Aero Precision Billet Trigger Guard, you have everything you need for your build.

This kit includes a takedown/pivot spring, detent, trigger/hammer pin, takedown pin, pivot pin, bolt catch, spring and buffer; a safety selector, spring and detent; a buffer retainer and spring; a billet trigger guard and roll pin; an ergonomic Magpul MOE pistol grip; screw and lock washer; a trigger spring as well as hammer spring and disconnector spring; plus a magazine catch body – complete with spring and button – along with a hammer, trigger, disconnector components.

  • Manufactured to mil-spec dimensions
  • Coated for quality assurance
  • Enhanced Lower Parts Kit offers an upgraded Magpul MOE Grip and Aero Precision Billet Trigger Guard
  • Magazine catch body – complete with spring and button – along with a hammer, trigger, disconnector components
  • Not Found


8# Aero Precision AR-15 Magpul MOE Lower Parts Kit

Aero Precision AR-15 Magpul MOE Lower Parts Kit

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Upgrade your AR-15 with the Aero Precision AR-15 Magpul MOE Lower Parts Kit and enjoy precision, reliability and versatility. This lower parts kit is designed to fit an Aero Precision Gen 2 or similar mil-spec lower receiver. It includes all the necessary components for assembly – such as a Magpul MOE Grip in Black or FDE – as well as a Magpul MOE Trigger Guard in either colour option.

With the Aero Precision AR-15 Magpul MOE Lower Parts Kit, you get a reliable and trusted build that offers accuracy, precision and versatility no matter what your mission calls for. Take control of your build and customize it to meet all your needs whether you opt for the tried and true fire control group or go with one of our upgraded trigger kits. Get the best parts available with this combination of MIL-SPEC grade components and high-quality accessories from Magpul.

  • Precision
  • Reliability
  • Versatility
  • May be too pricy for some users


9# Bravo Company Gunfighter AR-15 Enhanced Lower Parts Kit

Bravo Company Gunfighter AR-15 Enhanced Lower Parts Kit

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Replace or upgrade your AR-15 lower receiver with the Bravo Company Gunfighter AR-15 Enhanced Lower Parts Kit. This complete kit includes top-of-the-line Mil-Spec parts that have been engineered and built to offer unparalleled performance. The BCM PNT Trigger Assembly provides a smoother trigger pull while significantly reducing felt “creep.” The included BCM Pistol Grip, Mod 3, offers an aggressive texture to secure and enhance your grip while shooting.

In addition to those components, this kit also includes a BCM Enhanced Trigger Guard and various other parts renowned for their durability under use. All of these parts are guaranteed to meet Mil-Spec standards so you can trust them for any situation you encounter.

  • Superior quality Mil-Spec parts
  • Smooth trigger pull with reduced creep
  • Aggressive texture on BCM Pistol Grip Mod 3 for a secure grip
  • Meets Mil-Spec standards
  • May be difficult to install for those who are not familiar with AR-15s
  • Some users have reported incorrect installation of parts, requiring further modifications


10# Jacob Grey Firearms AR-15 Lower Parts Kits

Jacob Grey Firearms AR-15 Lower Parts Kits

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Jacob Grey Firearms bring you their premier lower receiver parts kit for the AR-15. Compatible with your favourite grip, stock, and buffer tube kit, this assortment of finely crafted components is an ideal addition to your next AR-15 build. Made to rigorous standards of quality and accessibility, each piece meets or exceeds Mil-Spec tolerances and offers a degree of precision that enthusiasts from all levels can trust.

Designed with customization in mind, assembling your own AR-15 gives you unparalleled control over this multi-functional platform. You can build it exactly how you want for use in hunting, target shooting, law enforcement operations, or even self-defence. With Jacob Grey Firearms’s complete lower receiver parts kit as part of your build process, you gain access to dependable components that facilitate a safer assembly experience.

  • Compatible with a variety of grips, stocks, and buffer tubes
  • Meets or exceeds Mil-Spec tolerances
  • Offers precision that enthusiasts from all levels can trust
  • Gives you unparalleled control over your AR-15 build
  • Not designed for everyone – customization may require some level of expertise


11# RISE Armament Lower Parts Kit

RISE Armament Lower Parts Kit

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Time to take your AR-15 to the next level with the RISE Armament Lower Parts Kit. Whether you need to replace a few pieces or rebuild the whole receiver, this kit is designed for maximum efficiency. It’s easy to install and comes with 20 parts specifically designed for AR-15-style rifles. Each piece undergoes rigorous testing and refinement, ensuring that it can handle even the toughest conditions.

The kit doesn’t include a trigger but does contain all of the necessary pins, safety components and more for reliable, seamless performance. A profession grade product from RISE Armament, you don’t have to worry about sacrificing quality for convenience when upgrading your firearm.

  • Easy to install
  • 20 pieces designed for AR-15-style rifles
  • Rigorous testing and refinement
  • Convenient and reliable performance
  • Quality construction
  • Trigger not included


12# WMD Guns AR-15/.308 Lower Parts Kit

WMD Guns AR-15/.308 Lower Parts Kit

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The WMD Guns AR-15/.308 Lower Parts Kit Mod 2 is the perfect solution for boosting the performance of your AR Rifle. This kit includes a NiB-X hammer, trigger, disconnect, bolt catch, mag catch, mag catch button, and safety selector paired with a front pivot pin, rear takedown pin, trigger guard assembly and essential pins and detents. As part of the Mod 2 iteration, this product also features nickel/black colouration in its NiB-X finish – perfect for delivering reliability against even the toughest of tasks.

  • Durable construction
  • Enhanced performance
  • Mod 2 iteration features nickel/black colouration for reliability
  • May be difficult to install for those without experience
  • NiB-X finish may not be to everyone’s taste


13# XTS AR-15 Lower Small Parts Kit AR-KIT

XTS AR-15 Lower Small Parts Kit AR-KIT

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The XTS AR-15 Lower Small Parts Kit is the perfect addition to your rifle. This kit from XTS is made of efficient and heavy-duty materials, making it exactly what you need for superior performance. Whether you’re a beginner shooter or simply looking to upgrade an existing rifle, this small parts kit from XTS is one of the best options on the market. It contains everything required for modifying your firearm, so you won’t have to shop around for separate pieces elsewhere.

Carefully designed with precision by top-class professionals, the parts in the XTS AR-15 Lower Small Parts Kit are guaranteed to provide optimal performance and durability on any rifle. With these expertly engineered elements working together as part of your system, you can hit targets with superior accuracy and confidence.

  • Durable construction for lasting use
  • Modification components included
  • Precision engineering for accurate shooting
  • Suitable for all rifles
  • May not be compatible with all rifles
  • Parts may wear out over time


14# TRYBE Defense AR-15 Mil-Spec Complete Lower Parts Kit

TRYBE Defense AR-15 Mil-Spec Complete Lower Parts Kit

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The TRYBE Defense AR-15 Mil-Spec Complete Lower Parts Kit is everything you need to complete your AR lower receiver build. This kit includes top-of-the-line products crafted with supreme precision and quality assured by mil-spec standards. The Bolt Carrier Group, Grip & Handstop, Charging Handle, and Muzzle Break feature sleek designs and robust performance so your completed rifle will look great and keep shooting in any conditions.

Upgrade your optics with TRYBE Optics for optimal long-range targeting, accuracy, and visibility. With the included 42” Rifle Case, you can easily transport your completed rifle to and from the range or outdoors without ever sacrificing protection from shocks or scrapes.

In addition, carry all of your shooting necessities in the extra-large TRYBE Tactical Range Bag that features a multitude of pockets that can be organized to fit anything from ammunition to snacks. Make sure you have all the essentials for thorough firearm maintenance when you get home as well as exotic wood oil stocks, lubricants for all applications, cleaning kits and much more!

  • TRYBE Defense AR-15 Mil-Spec Complete Lower Parts Kit is a high-quality product.
  • It is made of durable materials that will last for a long time.
  • The installation process is simple and easy to follow.
  • The kit comes with all the necessary parts and tools.
  • It is affordably priced.
  • May be difficult to assemble for those who are not familiar with firearms


15# Strike Industries AR Enhanced Lower Receiver Parts

Strike Industries AR Enhanced Lower Receiver Parts

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Take your AR15 to the next level with the Strike Industries AR Enhanced Lower Parts Package w/Trigger, Hammer & Disconnector. This bundle of AR15 lower parts from Strike Industries is designed to upgrade the function and quality of your weapon for a smooth shooting experience. The set includes a fire control group with a crisp 4.5-5.5 lbs pull for easier operation as well as critical components coated in a phosphate finish for superior corrosion and wear resistance.

The included enhanced bolt catch is completely redesigned with improved grip surfaces and angles to enhance performance when out in the field or on the range. For reliable parts that you can trust, rely on Strike Industries and their collection of enhanced lower parts packages perfect for any AR enthusiast searching for superior performance, exceptional function life, and lasting reliability no matter where you take your rifle.

  • Superior quality
  • Enhanced bolt catch
  • Crisp 4.5-5.5 lbs pull
  • The coating may not be as durable as other options


16# KAK AR-15 Lower Parts Kit

KAK AR-15 Lower Parts Kit

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Introducing the KAK AR-15 Lower Parts Kit, designed for serious rifle shooters and tactical professionals. This kit is made up of 100% USA parts, offering ultimate quality and performance. Each part is carefully developed to deliver precision accuracy and smooth operation every time you fire your weapon. The trigger group is mil-spec grade to provide reliable performance even under the most extreme conditions. Included in the kit is a black oxide finish on all springs for increased durability, providing extra protection against wear and tear.

The standard A2 handle ensures comfortable to use throughout your shooting training or competition. The KAK Billet Trigger Guard gives extra sustainment with improved ergonomics from its design which includes finger grooves and ridges. A common problem among other AR parts kits has been solved thanks to the rounded curves in the guard’s edges, which reduces snagging when reloading quicker than ever before.

  • 100% USA parts
  • Precision accuracy
  • Smooth operation
  • Mil-spec grade
  • Durable springs
  • A2 handle
  • KAK Billet Trigger Guard
  • May require some gunsmithing
  • Triggers are not adjustable


17# Tactical Superiority AR-15 Lower Parts Kit

Tactical Superiority AR-15 Lower Parts Kit

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The Tactical Superiority AR-15 Lower Parts Kit is an essential tool for any serious shooter. Featuring mil-spec components with superior reliability, accuracy, and durability, this kit provides excellent performance and a competitive edge to your build. With everything you need to complete a lower receiver, this kit contains a brand new bolt catch, magazine catch, pivot pin and spring, safety selector, bolt catch spring, magazine catch button, and even a magazine catch spring. From fast reloads to enhanced accuracy on the range or in the field, these parts provide superior craftsmanship that sets your rifle apart from the rest.

  • Superior reliability
  • Accuracy
  • Enhanced performance
  • Parts may wear out more quickly than their pricier counterparts


18# Zro Delta – Ar-15 Lower Parts Kit

Zro Delta - Ar-15 Lower Parts Kit

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The Zro Delta Enhanced Ar-15 Lower Parts Kit provides superior performance and durability for all your AR-15 gunsmithing needs. Easily assemble the framework of your lower with an awesome phosphate coating to keep it functioning better than ever and protected against corrosion. This kit contains everything you need to build and maintain your AR-15 minus the Trigger Guard, Grip, and Fire Control Assemblies. Not only do you receive grade-A parts in every kit, but they are also preassembled making installation quick and easy!

The unique design features provide unrivalled reliability that is perfect for any competition or recreational shooter. With our Enhanced LPK, you can create or customize a smooth working accurate assault rifle without breaking the bank. Now you can enjoy shooting with confidence knowing the parts inside your AR-15 were designed for superior performance with elite standards of quality at an affordable price.

  • Superior performance and durability
  • Easily assemble the framework of your lower
  • Grade-A parts with a phosphate coating
  • Corrosion-resistant design
  • Preassembled for quick and easy installation
  • Unrivalled reliability
  • Perfect for competition or recreational shooters
  • The coating may not be to everyone’s liking
  • Some parts may be prone to corrosion


19# Alg Defense – Ar-15 Lower Parts Kit W/ Qms Trigger

Alg Defense - Ar-15 Lower Parts Kit W/ Qms Trigger

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The Alg Defense AR-15 Lower Parts Kit W/ QMS Trigger is an easy and cost-effective way to get all the components you need for your tactical rifle. This complete lower parts kit comes with everything you need to build out a lower receiver, including a Bolt Catch, Mag Release, Safety Detent, Takedown Pins, Buffer Retainer, Trigger Guard Roll Pin and more!

Crafted from high-grade materials for optimal longevity and reliability–a must-have for any gun enthusiast or collector. And now it includes the QMS Trigger – providing a smooth 4.5 lb pull weight without sacrificing crisp trigger feel and performance. With the option of adding a grip, this kit is perfect for use in competitions or just out on the range practising accuracy drills.

  • Ar-15 Lower Parts Kit W/ Qms Trigger- Made in the USA
  • Quality construction and materials
  • Includes QMS Trigger for smooth, crisp performance
  • May require some gunsmithing for installation
  • Trigger pull weight could be lighter


20# Sharps Bros – Ar-15 Lower Parts Kit With No Fire Control

Sharps Bros - Ar-15 Lower Parts Kit With No Fire Control

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Do you want a reliable and high-quality AR-15 lower parts kit that gives you complete control over your rifle build? Look no further than the Sharps Bros. AR-15 Lower Parts Kit, allowing you to choose all of the components that fit your needs, truly making it uniquely yours. This set contains 100% USA-made components, manufactured to our exacting standards.

By cutting out the fire control group and overseas production, you can be assured each part meets the highest level of quality at an excellent price. Use this kit for various parts such as bolt catch, selector detent, magazine catch assembly pins, takedown pin, pivot pin detents, buffer retainers and a full spring kit. Make sure each piece fits your mil-spec dimension lower receiver with complete confidence in the end result.

  • 100% USA-made components
  • Manufactured to our exacting standards
  • Complete control over your rifle build
  • Various parts such as bolt catch, selector detent, magazine catch assembly pins, takedown pin, pivot pin detents, buffer retainers and a full spring kit
  • Can’t choose individual parts
  • No fire control group


Installation 🎯

🛠️ Before you begin, it’s important to have all the necessary tools and items available. You’ll need a vice block, a pin punch set, a small hammer, pliers, and various Allen wrenches to complete installation. Also, make sure that you have all the components for your Lower Parts Kit readily available.

✅ Start by setting up your work area with the correct supplies. We recommend placing your receiver into a vice block for stability during installation. ⭕ If you don’t have one, you should be able to find one at most gun stores or online retailers.

✅ Now that your work area is set up correctly, begin installing each component from your Lower Parts Kit into its designated place on the lower receiver. Start by inserting the takedown pins into their respective places at either side of the receiver before moving on to other components such as triggers and safety selector switches. ⭕ Make sure to use proper force when pushing them in; using too much force may cause damage to pins or receivers themselves!

✅ The trigger guard will also need to be installed prior to proceeding with other components in order for it to fit correctly later on. To do this, press both sides of the guard through their respective holes located near the front portion of the receiver before tightening them down with Allen wrenches provided in your kit (or better yet – use an AR-15 armourer tool!).

✅ When everything else has been installed correctly and securely into place, move on to testing out the function and safety of all parts on your newly built lower receiver assembly! ⭕ Take time to check that each component works as expected – inspect triggers for smooth pulls, safeties for clean engagement/disengagement operations and pins/levers for proper tensioning when manipulating them manually using just hands or pliers if necessary!

✅ With everything tested out successfully, all that’s left is tightening down screws/nuts where applicable and applying some thread locker or oil on exposed threads if desired (not recommended). Congratulations – you now have a fully functional lower parts kit AR 15 installed on your rifle! ⭕ Enjoy it responsibly!

Watch this video to find more information 💻


How to choose the highest-quality AR-15 parts?
Choosing the highest-quality AR-15 parts is an important and necessary task if you want to ensure that your rifle functions properly and performs at its highest level. When selecting components, there are a few key points to keep in mind that can help guarantee you wind up with the best possible parts for your AR-15 build.

⚪ First off, it’s essential to consider what kind of quality assurance measures have been put into place by the manufacturer. Quality control is a vital component of any part manufacturer and will give you an idea of how much care has gone into each component. ✔️ Look out for certifications such as ISO 9001:2015 or MIL-STD-1913, which will indicate that tests have been conducted to confirm the reliability and safety of each part.

⚪ In addition to looking at certifications, also make sure to check what materials have been used for each component of the lower parts kit. The majority of components in an AR-15 should be made from high-grade steel or aluminium alloy; the higher-grade material will typically result in better performance and longer life expectancy for each part. Steel components with receiver extensions are highly recommended since they are designed for maximum strength and durability.

⚪ It’s also wise to consider how compatible your parts will be with other components in your rifle build. Most lower kits come with everything needed for completion, but certain pieces may not work correctly when combined with other parts due to variances in dimensions or design discrepancies between manufacturers. ✔️ Make sure to double-check all measurements before starting installation so that any issues can be addressed immediately rather than after assembly is complete.

⚪ Finally, when choosing a lower parts kit take a look at user reviews online that offer real feedback from people who have actually used a particular model or brand before making your final decision. ➡️ This can provide valuable insight into both product quality and customer service levels if something were to go wrong during assembly or shortly afterwards.

What is an enhanced lower parts kit?
An enhanced lower parts kit is designed to provide a more comprehensive selection of components that are necessary for the completion of an AR15 rifle. This type of kit typically contains everything needed to complete an AR15 build, including enhanced components such as extended mag releases, extended safety selectors, and improved trigger assemblies. These enhanced lower parts kits offer the shooter a more personalized experience when customizing and building their own AR15.

🟡 Enhanced kits give builders the freedom to choose from a larger range of customized options for their specific needs.

  • For example, some kits come with upgraded fire control groups which can offer smoother triggers or lighter reset springs.
  • Other kits can include adjustable gas blocks which allow you to fine-tune your gun’s cycling characteristics for better performance on varied platforms such as sporting and tactical rifles.

🟡 In addition to improved components, they provide better reliability than standard factory lower parts by featuring high-quality materials that are designed to last longer under extreme conditions. Many enhanced lower parts are machined from aluminium or stainless steel, whereas standard lowers are usually made out of inferior polymer materials. ➡️ This ensures that your rifle will remain reliable even after thousands of rounds have been fired through it.

🟡 Furthermore, some enhanced sets may feature anti-walk pins and other enhancements which improve accuracy by preventing movement between the upper and lower receivers while shooting.

Are all AR-15 Small Parts Kits the Same?

When our team set out to research and recommend the best AR-15 lower parts kits, we quickly realized that not all kits are created equal. There can be major differences between kits in terms of component quality, features, manufacturing, and even country of origin. We’ve assembled rifles from cheap bare-bones kits all the way up to premier kits packed with upgrades. Through extensive hands-on testing and evaluation, we’ve identified what truly makes a lower parts kit stand out.

✔️ At a minimum, a kit must contain all the required components like the trigger group, safety selector, magazine release, bolt catch, pins, and springs. ❌ However, we found that factors like the quality of the machining, the material used for the parts, the included grip style, and the type of trigger can really separate the great kits from the more basic ones.

For instance, a single-stage match grade trigger provides a much cleaner, crisper trigger pull compared to a standard mil-spec trigger group.

🟢 Attention to detail also matters when it comes to components like the pins and springs. We’ve seen some lower-cost kits skimp here, using less durable pins that walk out of place or springs prone to breaking. The best kits use stainless steel pins and springs that hold up better over high round counts. Other customizable features like ambidextrous safeties and extended bolt releases provide functional benefits depending on your shooting style.

We believe this video can be helpful for you 📺

What finishes are available for lower parts kit components?
Types: Description:
Parkerizing ☑️ This matte grey finish is done through a phosphate treatment. It provides moderate corrosion resistance and a basic level of protection. Parkerizing is a common finish for mil-spec parts.
Nickel Boron ☑️ Nickel boron is an electroless nickel coating that creates a super smooth, slippery nickel finish. This aids in cleaning, resists corrosion, and reduces friction. The nickel boron process can be done in various colours as well.
Cerakote ☑️ A popular thin-film ceramic coating that comes in a vast selection of colours. It is very abrasive and corrosion-resistant. Cerakoting gives parts a brand-new personalized look.
Anodizing ☑️ The aluminium components like the trigger guard and magazine release can be anodized, which is an electrolytic process that creates a surface oxide layer. This makes a highly durable, scratch-resistant finish. Colours like black, grey, olive drab, and others are options.
NP3 ☑️ A proprietary nickel-Teflon finish that provides the lubricity of nickel boron but with a slightly greyer hue. The addition of the Teflon powder further slicks the surface.
Black Nitride ☑️ This finish diffuses nitrogen into the metal surface giving a matte grey/black appearance. It increases surface hardness and provides excellent corrosion resistance.
What are the parts of AR-15 Lower Part Kit?
❇️ Trigger Group
  • This includes the trigger, hammer, disconnector, trigger and hammer pins, and trigger and hammer springs. The trigger provides the lever that is pulled to fire the rifle.
  • Single-stage and two-stage triggers are available.
  • The hammer strikes the firing pin when released by the trigger. The disconnector catches the hammer after it strikes the firing pin to reset the trigger. The springs provide tension to reset the trigger and hammer.
❇️ Safety Selector
  • The safety toggle switches the rifle between safe “S” mode, fire “F” mode, and automatic “A” mode on select-fire rifles.
  • Non-ambidextrous selectors are located on the left side, ambidextrous have levers on both sides.
  • The selector rotates the disconnector to catch or release the hammer.
❇️ Magazine Catch
  • This part holds detachable magazines in place and releases them when actuated. The magazine catch button is pushed from the right side to drop magazines.
  • Some are larger or extended for easier activation.
❇️ Bolt Catch
  • The bolt catch engages and holds the bolt open after the last round is fired.
  • The paddle can be actuated to release the bolt and chamber another cartridge.
  • Enlarged bolt catches may be easier to reach for some shooters.
❇️ Pins
  • The trigger and hammer pins pivotally hold those parts in the receiver. They are normally standard diameter but anti-walk pins tightly fit to prevent movement.
  • The magazine catch and bolt catch pins retain those components.
❇️ Springs Small springs provide tension to reset the trigger and hammer in their forward positions after firing. They are made from steel or sometimes stainless steel for corrosion resistance.
❇️ Detents  These tiny spring-loaded balls help retain the takedown and pivot pins in place. They fit into small holes in the receiver.

🟨 It’s important to note that LPKs may vary in terms of the specific components included and their quality. Some LPKs are basic, while others may include upgraded or enhanced parts for improved performance or ergonomics.

🟨 Additionally, LPKs may be designed for specific AR-15 platforms, such as mil-spec or commercial-spec buffer tubes, so it’s essential to choose one that matches your build and preferences.

⚠️ Remember that adding these optional components may increase the overall cost of your build, but they can enhance the performance, comfort, and functionality of your AR-15 according to your specific needs and preferences.

Conclusion 🤩

Choosing the right lower parts kit is one of the most important decisions when building or upgrading an AR-15 rifle. While all kits contain the basic components, we’ve found the quality, features, and manufacturing can vary drastically.

Based on extensive testing and evaluations, we recommend focusing your search on kits offering enhanced triggers, American-made parts and corrosion-resistant coatings. The small upcharge over basic kits pays dividends in the long run through improved performance and reliability.

With the right tools and proper assembly, installing a lower parts kit is a straightforward process for most enthusiasts. Just be sure to follow the steps carefully and do not force any parts. A bit of patience during the build will reward you with a smoothly functioning rifle that will deliver many years of accurate shooting and trouble-free service.

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6 months ago

I am a big Aero Precision fanboy. I adore their LPK which leaves out the FCG and safety since

    6 months ago

    I’ve had good experiences with the Aero Precision lower parts kits. They offer solid quality without breaking the bank. Plus, they often have sales, so keep an eye out for those deals.

      6 months ago

      HI! Are LPKs compatible with both forged and billet lower receivers?

        6 months ago

        Is there a noticeable difference in lower parts kits for those of you with more experience in AR-15 builds? Personally, I’ve used both CMMG and Colt kits without any issues. I’m curious if there’s a preference among seasoned builders for specific brands or kits.

          6 months ago
          Reply to  Pridefire

          While Geissele LPKs are indeed on the pricier side and boast exceptional quality, functionally, you might not notice a substantial difference compared to a more budget-friendly option like CMMG.
          I personally opt for Geissele components for certain critical parts like the trigger, trigger guard, mag release, and more. For safety selectors, I prefer Radian or BAD. I tend to go with cheaper but reputable brands for smaller parts, springs, and detents like CMMG or AR-Stoner. Receiver extension nuts and plates also fall into the budget-friendly category. I like the Vltor A5 buffer system, but I switch between a GeisselSuperer 42 and JP polished rifle length spring. My grip of choice is the Ergo deluxe, but that’s purely a matter of personal preference.

            6 months ago
            Reply to  Pridefire

            It really comes down to the purpose of your build. For casual plinking, I wouldn’t break the bank on a lower-tier AR. CMMG is a solid choice, especially if it suits your needs. However, if you’re looking for top-tier quality and performance, investing in brands like Geissele can make a noticeable difference. I certainly experienced an upgrade in my own build. Ultimately, it’s all about weighing the cost against the benefit you’ll get from your investment.

              6 months ago
              Reply to  Pridefire

              In my view, if you’re going beyond Anderson or CMMG for higher-tier components while sticking to mil-spec parts, you might be paying an avoidable premium for the brand.

                6 months ago

                Hello! What types of trigger assemblies are commonly included in lower parts kits?

                  6 months ago
                  Reply to  Lensin

                  I recently bought an AR-15 LPK and was pleasantly surprised by the included single-stage trigger. It’s not too heavy, and the break is crisp. Great for range days and plinking!

                    6 months ago
                    Reply to  Lensin

                    I’m a fan of two-stage triggers myself. They provide excellent control for precision shooting. Just swapped out the mil-spec trigger in my LPK for a Geissele two-stage, and the difference is night and day