Best AR-15 Build Kits: Top 5 Picks for 2021

The AR-15 has arguably become one of the most popular rifle styles on the market today. Born years ago, for military use, the civilianize version of this rifle has become commonplace among rifle enthusiasts, hunters, and competition shooters. The modular format of the AR-15 platform lends itself to customization, allowing shooters to personalize their rifles.

Nothing gets more personal than assembling your own rifle. For many years, a custom-built rifle was the domain of gunsmiths and those with enough money to hire one. Not so with the advent of the AR-15 and the plethora of aftermarket parts and accessories. Building your AR-15 is easy and relatively inexpensive.

Before you embark on the ar-15 build adventure, there are some things to consider. Some of these factors depend on your level of ability and your knowledge of the AR-15 platform. For the novice, who is considering building their first AR-15, our recommendation is to buy a kit. A kit ensures that you will have all the parts you need to build a functioning rifle with no problems. In this article, I will look at some of what I consider to be the best AR-15 build kits on the market.

Choosing an AR-15 Build Kit: Top 5 Picks

Before you start shopping for your AR-15 build kit, there are some things to think about, especially if this is your first AR-15 build.

  • Establish a budget – Before you do anything else, work on your budget. Figure out how much you want to spend. A budget for your build will help you keep things from getting out of hand. Otherwise, you may find yourself spending much more than you anticipate on your parts as you shop. 
  • Decide on your rifle style – Knowing what you want your AR-15 to look like at the end of your build will keep you focused on the style and type of kit you want to purchase. If you want one of the variants that require a federal tax stamp, you must have your paperwork in order before you start assembling the parts to the final working rifle.
  • Choose a caliber – The caliber choices in an AR-15 platform are almost as broad as the accessories and styles. The most popular choice is .223/5.56 chambering. The .223/5.56 is the caliber we will focus on for this article.
  • Parts. Kits, Or Assembled Sections – If you are ambitious, you can certainly start buying individual parts. However, if this is your first build, we advise against trying to assemble an AR-15 by purchasing individual parts. You might save a bit of money, but the reliability of your rifle may suffer. Our suggestion is to purchase a build kit. You can find these fully unassembled to complete operational parts that simply need fitting together and the take-down pins closed.

Of Upper and Lowers

Ar-15’s have an upper and lower assembly. The upper assembly consists of the barrel, the upper receiver, and the bolt carrier group. The upper is unserialized and can be purchased easily. The lower receiver consists of the trigger control group, the buffer tube, spring assembly, and the safety. The lower receiver has the serial number, and the purchase requires a licensed firearms dealer.

Assembled Uppers – Bolt Carriers and Barrels

When you shop for an upper build kit, pay particular attention to what the kit includes. Many companies selling barreled upper receivers don’t include the bolt carrier group with the kit. There is nothing wrong with this, but it can be frustrating to find that the bolt carrier groups are missing as you are putting your parts together. 

One advantage to purchasing an upper receiver with the barrel installed is the problem of head spacing. Headspace is the measurement from the bolt face to the shoulder of the chamber. If the headspace is too tight, the gun will probably not go into battery after repeated firings and space becomes coated with carbon. 

A headspace that is too large and the round may back out of the chamber. A round that moves backward can damage the bolt or cause a malfunction. Most reputable dealers will headspace check their barreled upper assemblies before packaging and selling. 

You can purchase headspace gauges if you want to install your barrel yourself. While not expensive, the process of headspacing can be tedious and frustrating. I find it much easier to simply buy an upper receiver with a barrel installed and headspaced.

On To the Good Stuff

With the preceding information in mind, let’s get on to the good stuff and look at some of what I consider the best AR-15 Build Kits available. I will look at upper kits and lower kits. Remember that my choices may not meet your needs and expectations. You should do your research as well and make the decisions that fit your situation.

Best AR-15 Unassembled Kit – Palmetto Arms Rifle Kit Review

Palmetto Arms has been my go-to source for the last few AR-15 builds I have done. The customer service, the quality of the parts in their kits, and the competitive pricing have earned my business. This USA-based company focuses on quality parts sourced as locally as possible to ensure control of the process from start to finish.

The Palmetto Arms PSA 16” Carbine kit won’t disappoint even the most experienced AR-15 builder. A look at the included parts and the features will convince almost anyone that these are quality kits that will produce a quality rifle.

  • 4150V chrome-moly steel barrel chambered for 5.56 NATO
  • 1:7 twist barrel with an M4 barrel extension
  • Nitride treated for durability and long-life
  • Carbine length gas system with a low profile gas-block
  • M-Lock free float barrel rail and an A2 flash hider
  • The upper is forged from 7075-T6 A3 and features hard-anodized coating in black
  • M4 feed ramps cut into the upper receiver
  • The upper comes preassembled with the barrel installed and headspaced, and the ejection port cover installed.
  • Complete with the rail assembly and gas system in place.
  • Includes the complete bolt carrier group, charging handle, and lower receiver parts kit
  • The lower receiver is not included and must be purchased separately.

I like these kits for several reasons. Mostly, for the novice AR-15 builder,  these kits offer the advantages of putting together parts that are known and tested to work well together. The novice builder also gets the support of Palmetto Armory if problems do crop up. A phone call will get you someone who knows and understands AR-15 builds and can quickly get you back on track.

Best AR-15 Stripped Upper – Aero Precision Review

If you intend to start bare bones and assembling your AR-15 from scratch, the first part to consider is the upper receiver. There are hundreds of manufacturers of stripped upper receivers. You won’t do any better for my money for a first time build that staring with an Aero Precision stripped upper.

Many AR-15 enthusiasts consider Aero Precision uppers to be the gold standard in the industry. I am not sure about that, but many of the AR-15’s I have built use an Aero Precision upper. You can get Aero Precision uppers in many different configurations to suit your needs.

  • Machined in the USA
  • Forged from 7075-T6 aluminum
  • Milled to Mil-Spec dimensions
  • M4-Feed Ramps
  • .250 takedown pin holes
  • Laser engraved T-marks on the rail
  • Black anodized finish (other colors available)

Best AR-15 Complete Lower Kits – Aero Precision Standard Review

Aero Precision makes excellent AR-15 parts. For the money, the best lower parts kit available is the Aero Precision Standard Lower Parts kit. The standard lower parts kit is the baseline parts kit put together by Aero Precision, and for a first-time AR-15 builder, it is a great choice. 

The quality of the parts in this Aero Precision kit is unquestioned. The low price makes this kit my choice for the best complete lower parts kits available. There are more expensive options, but for a basic AR-15 build, you don’t want to start with expensive trigger groups or other accessories. The Aero Precision Standard lower parts kit includes:

  • All Mil-Spec dimensions
  • Mil-Spec coatings
  • Includes the following parts:
    • Takedown/pivot Spring
    • Takedown/pivot detent
    • Trigger/hammer pin
    • Takedown pin
    • Pivot pin
    • Bolt Catch
    • Bolt Catch Spring
    • Bolt Catch buffer
    • Bolt catch roll pin
    • Safety Selector
    • Safety Selector spring
    • Safety Selector detent
    • 4-40 Set Screw (for threaded takedown pin detent hole)
    • Buffer retainer
    • Buffer retainer spring
    • Trigger guard
    • Trigger guard roll pin
    • A2 pistol grip
    • Pistol grip screw
    • Pistol grip lock washer
    • Trigger spring
    • Hammer spring
    • Disconnector spring
    • Magazine catch body
    • Magazine catch spring
    • Magazine catch button
    • Hammer
    • Trigger
    • Disconnector

If you are assembling your AR-15 rifle from stripped uppers and lowers, the Aero Precision standard lower parts kit is a good starting point to assemble your new lower receiver.

Best Complete AR-15 Lower – Palmetto State Armory Review

The convenience of ordering an assembled complete lower kit is not to be dismissed. Getting a trigger assembly, magazine catch, safety, and buffer tube installed can be daunting. The number of small detent pins and springs alone can be a nightmare. 

The Palmetto Armory Complete classic stealth lower offer the first time AR015 builder the best in parts and quality without the headaches of pins, detents, and springs. Simply open the box, push out the takedown pins, and put the upper in place. A complete assembled lower gives you an almost instantly ready to go to the range AR-15.

You won’t be disappointed in the features or quality of the PSA lower either.

  • Machined from 7075-T6 aluminum
  • Hard coat anodized finish to Mil-A-8625F, Type III, Class 2 standards
  • Mil-Spec diameter receiver extension
  • M4 Stock included
  • Staked M4 Lock Nut
  • Standard carbine buffer
  • Un-notched hammer
  • Labeled as multi-caliber

The PSA complete classic stealth lower may be considered a budget complete lower receiver, but it is a great foundation to start your AR-build. The quality and workmanship on this receiver allow you to expand and accessorize your AR-15 to your heart’s content.

Remember that the lower receiver is the serialized part of your AR-15 rifle. Any lower you purchase online must be shipped to a licensed FFL dealer to complete the transaction.

Best Stripped AR-15 Lower Receiver – Anderson Manufacturing Lower Receivers Review

If you are building a frankengun (an AR-15 assembled from various manufacturer’s parts), then using an Anderson stripped lower receiver is a great choice. Anderson build some of the most affordable lower receivers on the market. The great thing is Anderson doesn’t skimp on the materials or the quality of the machining.

Most of my builds fall into the frankengun category. I am a fanatic about shopping price, but I also demand quality from the parts I use. The Anderson lower receivers meet all these qualifications and have never let me down. For the price, the features offered by Anderson are unbeatable in my book.

  • Mil-Spec machining to all dimensions
  • Ulti-Cal engraving
  • Semi-auto design
  • Available with no logo
  • Machined from 7075 T6 Forgings
  • Type 3 hard-anodized finish
  • Accepts both 3/4 inch and 1-inch grip screws

For frankengun builds, the Anderson Manufacturing lower receivers offer the first time builder and economical way to have the best in quality and performance. For a basic AR-15 build, I don’t think you can make a bad choice with an Anderson lower receiver.

Building Your Ar-15 – Fun, Exciting, and Educational

Building your first AR-15 fills many different parts of your shooting hobby. Building a new rifle is probably the best part. Shooting something that you built and tuned is ultimately satisfying. Add to the satisfaction the knowledge you gain about the parts and operation of your rifle. You ultimately become a better shooter. 

I hope that this article has given you a solid foundation for knowledge on which to build as you begin to build your AR-15. Of course, this not a comprehensive guide or list of AR-15 kits. You must do your research and find the kits or parts that best fit your needs and expectations. If you have ideas, experiences, or knowledge, please share it in the comments section below. Good shooting and have fun.


You may also like

Comments are closed.