Are you currently looking for the best parts kit for your M16A1 rifle? If so, you’ve come to the right place.
Best Overall: Palmetto State Armory LPK-E Parts Kit
The Palmetto State Armory LPK-E Parts Kit is our top choice for an M16A1 parts kit. The big standout feature of this kit is the two stage combat Geissele Super semi-automatic trigger, which is the same trigger that SOCOM units in the American military use in their AR-style rifles.
Best Lower Receiver Parts Kit: Colt Lower Receiver Parts Kit
The Colt Lower Receiver Parts kit is one of the best lower receiver parts kits on the market. Built to mil-spec tolerances from the Colt factory, this kit comes with everything that you need other than the pistol grip and trigger group. An accu-wedge is also included to reduce wobble between the lower and upper receivers and increase accuracy out of your rifle.
Best Upper Receiver Parts Kit: Aero Precision AR-15 Upper Parts Kit
The Aero Precision AR-15 Upper Parts Kit comes with everything that you need to complete your M16A1 upper receiver. The components are each built out of aircraft grade 7075 aluminum and are built to mil-spec tolerances as well.
The M16A1 is the original M16 like was used by the American military in Vietnam and paved the way for the rest of the AR platform as a whole. It’s a classic weapon that is still very versatile to this day.
If you are looking to build a new M16A1 from the ground up or otherwise improve your existing one, then having a quality parts kit will be a necessity. Furthermore, it can also be wise to invest in a parts kit just to have extra components for your M16A1 on hand.
In this guide, we’ll dive into the history of the M16A1, the different components that are included in a parts kit, the top qualities to look for in a kit, and then our choices for the top three best M16A1 parts kits for 2021.
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What Is The M16A1?
The M16A1 is well-known as the original AR-15. It was the rifle that formally replaced the M14 rifle and was issued to American servicemen in Vietnam.
The original AR-15 rifle in 5.56x45mm NATO was designed by Eugene Stoner as a scale down version of his earlier AR-10, and was first manufactured by Colt. It was given the designation M16A1.
The M16A1 was adopted because it was determined that the M14 was too large and heavy for the standard American infantrymen. The M14 itself was nothing more than a modified M1 Garand like was used in World War II. Initially used in the early years of the Vietnam War, the M14 proved to be a fine rifle but it was also simply too long and heavy in the dense jungles of Vietnam. The 7.62x51mm NATO ammunition it fired was also too large and kicked too much for most soldiers engaged in tight close quarters combat.
Enemy North Vietnamese troops were using the smaller AK-47, and the American military quickly decided that their troops needed a similarly sized rifle.
The M16A1 offered many advantages over the M14 rifle. It was smaller and lighter than the M14, and therefore more inherently wieldy. It also carried more ammunition, and the 5.56 round that it fired also produced less recoil and was therefore more controllable. The average American soldier could carry greater firepower with the M16A1 in a smaller and easier to shoot package.
The early M16A1 rifles are easily distinguishable even to this day because of their triangular handguard and three pronged flash suppressors. The original M16A1s were also issued with 20 round STANAG magazines, but the 30 round magazines will work in them just fine. The military themselves later upgraded from the 20 to 30 round magazines only a few years after the Vietnam War concluded.
Since the initial release of the M16A1, it has gone through several evolutions, including as the M16A2, M16A3, and most recently the M16A4. Today, the M16 series has primarily been withdrawn from frontline service in favor of the more compact M4 series of rifles.
AR-15 rifles have today become very popular amongst American civilians well, to the point that the AR-15 is now the most popular centerfire rifle sold in the United States. There are many reasons for this: the AR-15 is very ergonomic, reliable, accurate, and easily customizable.
Today, the M16A1 style of AR-15 in particular has seen a small but notable resurgence in the hands of American citizens. Companies such as Brownells have released what are called “M16A1 retro rifles”, which are essentially modern day rifle length AR-15s with the appearance of the M16A1 (such as the three pronged flash hider and the triangular handguard).
If you want a modern day AR-15 that closely mimics the look and the feel of the original M16A1s like were used in Vietnam, the retro-style M16A1s are excellent choices. There are also many reasons to consider going with the original style M16A1 rather than a more modernized AR-15.
One reason is you may simply desire having the original style of M16A1 for no reason other than that you want the more classic design. Another more practical reason to consider the M16A1 is if the triangular handguard is naturally more ergonomic for you.
But of course, if you want an M16A1 you don’t have to necessarily buy one outright. Instead, you could purchase each of the components that you need separately in order to assemble your M16A1 from the ground up. The latter approach may be actually more feasible considering the fact that there is a major shortage of firearms going on right now.
If you are planning to build a new M16A1 rifle from the ground up or otherwise upgrade your existing one, something that you will need is a parts kit. What is a parts kit? That’s what we’re going to discuss next.
What Is A Parts Kits?
A parts kit is exactly what the name suggests: a simple collection of parts needed to help assemble your AR-15 or M16A1. However, parts kit can vary significantly from one another in terms of which parts are actually included.
First and foremost, parts kits can be usually divided into upper receiver and lower receiver parts kits. It’s very rare that a parts kit will be sold with both upper receiver and lower receiver parts in it at the same time.
Further complicating things is how either an upper or lower receiver parts kit may not come with everything that you need to complete either the upper or lower respectively. For example, your lower receiver parts kit may not come with literally everything that is needed to turn a stripped lower into a complete lower.
This is why it’s up to you to carefully research which parts are included in your parts kit of choice. It’s very common for lower receiver kits, for instance, to come with literally every component that you need to complete your lower with the exception of the trigger guard and the pistol grip. With upper receivers it’s a similar story, as many will come with all of the components needed to complete the upper other than the forward assist and the ejection port cover.
Again, research what is included in your kit and what is not included. Anything not included will need to be purchased separately.
Why Do You Need To Buy A Parts Kit?
There are two main reasons to consider buying a parts kit. The first reason is if you are assembling a new rifle from the ground up and if you will be purchasing a stripped lower or a stripped upper. Purchasing a parts kit will not be necessary in this scenario if you are purchasing a complete lower or upper because you won’t need any additional parts to get the rifle functioning.
However, stripped uppers or lowers will require more components installed to get them functioning. While you can purchase all of these components separately if you so choose, by buying a parts kit instead chances are good that you can buy the pieces that you need for less money per part.
The other reason to buy a parts kit is to have additional parts on hand for repairs or replacements. This isn’t a particularly bad idea, especially when you consider that there is a major shortage of firearms and firearm-related accessories going on as of the time of this writing. This means that if your M16A1 or AR-15 suffers damage and needs new components, it may not be so easy to buy the components that you need. By purchasing a parts kit and then setting it aside in storage, you’ll ensure that you have the required parts in the event of future needed repairs.
Buyer’s Guide For M16A1 Parts Kits
These are the most important factors to consider when looking for a new parts kit for your M16A1:
No Gunsmith Required For Installation
First and foremost, the parts included in your parts kit should not require the aid or services of a gunsmith to install in your M16A1’s upper or lower receivers. If the parts kit is labeled as a ‘drop-in design’ it means that no gunsmith or spare tools are required to install the pieces.
Go With A Combat Trigger
If your parts kit comes with a trigger, you’ll ideally want to make sure that it’s a military trigger. A two-stage combat trigger is considered to be the gold standard. Alternatively, you can go with a match grade trigger, which will be much lighter and crisper through at greater expense.
The components to an AR-15 made rifle, and particularly in the upper and lower receivers, are usually built out of both steel and aluminum parts. Avoid the use of polymer for the internal components for your M16A1.
All Parts Included
Last but not least, research which specific parts are included in your parts kit! Remember that while some parts kits will come with literally everything you need to complete either your lower or upper receiver respectively, most part kits will lack everything that you need. It’s your responsibility to research which parts are included in the kit as listed by the manufacturer.
The 3 Best M16A1 Parts Kits For 2021
Now that we’ve covered why you need to upgrade your M16A1 with new parts kits and what to look for in a kit, here are our top three choices for an M16A1 parts kit in 2021:
Colt Lower Receiver Parts Kit
The Colt Lower Receiver Parts Kit is a set of genuine Colt-made lower receiver parts. Considering that Colt was the original manufacturer of the M16A1 as issued to American soldiers in Vietnam, by using the parts in this kit you can replicate the original M16A1 more closely.
There is no trigger, trigger group, or pistol grip included in this lower receiver parts kit, so you will need to purchase those items separately. However, all other parts that are needed to complete your lower receiver are included in this kit. What’s more, is that each part is packed separately to ensure that it will be kept secure and unharmed during shipment.
Another piece that is sold as a part of this kit is the Accu-Wedge, which is a rubberized insert that goes beneath the rear takedown pin. Many owners of the AR-15 argue that this piece will effectively prevent movement between lower and upper receiver and therefore aid in accuracy.
All in all, the Colt lower receiver parts kit is a solid choice if you need a basic parts kit for your M16A1. All of the components included in this kit are genuine Colt factory parts, which can help you to more closely replicate the original M16A1 design. Just be aware that you’ll need to buy the trigger group and pistol grip separately.
- All parts are genuine Colt factory
- Each part comes packed separately
- Built to mil-spec standards
- Includes an accu-wedge
- No trigger group or pistol grip included
Aero Precision AR-15 Upper Parts Kit
The Aero Precision AR-15 Upper Parts Kit comes with all of the components that you need to complete the upper receiver to your M16A1. The specific components that are included in this kit are the forward assist assembly, forward assist spring, forward assist roll pin, ejection port cover spring, ejection port cover rod, and the port cover door.
All parts are built out of high quality aircraft grade 7075 aluminum with a matte black finish. The components are also all built to mil-spec specifications and are intended to be installed without the aid of a gunsmith, which is a major plus.
Overall, the Aero Precision AR-15 Upper Parts Kit will be a solid choice for your M16A1’s upper. All of these components are built to mil-spec tolerances just like the original M16A1, and everything that you need to complete your upper receiver is included.
- Comes with all components that you need to put together an AR-15 upper receiver
- Built to mil-spec tolerances
- Does not require the services of a gunsmith to install
- Built out of 7075 aluminum
- Matte finish is not the most appealing
Palmetto State Armory LPK-E Parts Kit
The Palmetto State Armory LPK-E Parts Kit comes with everything that you need to complete your M16A1 lower receiver, including the trigger and the pistol grip. The trigger in particular is a real standout, as it’s a Geissele Semi-Automatic Enhanced Trigger that is the same combat trigger utilized by the United States SOCOM units.
The pistol grip itself is a standard A2 grip like is used on standard military M16 and M4 rifles. All components are built out of high quality aircraft grade 7075 aluminum and are also built to mil-spec standards. While you will pay a premium price for this kit, you’ll be comforted in knowing that you’re getting a military grade kit that will last for a lifetime. Furthermore, all pieces are designed to be installed by the user without the services of a gunsmith.
The Palmetto State Armory LPK-E Parts Kit is an absolutely solid choice for a parts kit for your M16. Built to last thanks to the mil-spec 7075 aluminum, the real standout is the two stage Geissele Super semi-automatic trigger that is the same combat trigger used by SOCOM units in the United States military.
- Comes with a nice combat two stage Geissele Super semi-automatic trigger
- All components are built to mil-spec standards
- Built out of 7075 aluminum
- Does not require the services of a gunsmith
- Includes everything that you need to complete the lower receiver
- Very expensive
You’re bound to have a lot of fun with your new M16A1 AR-15. If you want an AR-15 that is built as close as possible to the original Colt M16A1 like was used by American soldiers in Vietnam, it’s very important that you buy the highest quality components that are very similar to what were originally used.
The parts kits that we have covered in this guide can be used to either upgrade your existing M16A1 or otherwise help you build a new M16A1 from scratch. Using the parts kits that we have covered here together will be to your biggest advantage, or alternatively you can look for more parts kits based on the buyer’s guide section that we covered before as well.
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