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Building An 80% Firearm- Part 1,

by Tupreco SurvivalBlog Contributor | March 7, 2017

Learn the Why and How

The election of Donald Trump is beginning to show concrete steps toward dialing back the Obama administration’s numerous efforts to undermine our Second Amendment rights. How that will continue to play out remains to be seen. Surprisingly though, even on Obama’s watch there were several pro-2A court and legislative victories, including expansion of concealed carry in many states.

Another thing that occurred while Obama was in office was an unexpected but welcome surprise from the ATF. Several years ago, a well-known AR-15 parts manufacturer requested and received the ATF’s formal approval to manufacture and sell, without restriction, a partially-finished AR-15 lower receiver. This receiver would only be legal for unrestricted sale if the ATF approved the exact design where several very specific features remained un-machined or marked in a way that would aid in its completion. This partially-complete receiver (now commonly called an “80% receiver”) required that the through holes for the trigger and hammer pins be omitted and that solid material must remain where the cavity for all of the trigger components would normally be milled out. This new approach was clearly designed to attract buyers who would then complete the steps left unfinished. When finished, it would be a fully functional AR-15 lower receiver.

Many people don’t realize that it has been legal for years to build your own personal unregistered firearm. Up to this point, the practice of making a homemade firearm has not generated much activity or interest for two reasons. First, a home built firearm cannot be legally sold or transferred to another person. Second, building a firearm safely was typically well beyond the skills of most people. However, the approval for sale of a partly finished receiver ushered in a significant change. Now all that would be required to build a quality firearm at home would be a minimal level of machining skills and equipment. Suddenly, making your own unregistered firearm for only personal use just got a lot easier. Virtually overnight, the 80% firearms industry was born and has continued to flourish. It will surely continue to grow, provided it is not eliminated through a contrary stroke of the ATF’s regulatory pen.

This may be the time to take advantage of the opportunity to build your own “ghost gun”, as this type of firearm is often called. For now you can build your own commercial-quality firearm with virtually no paper trail tracking it (presuming you don’t use your credit card or ship to your home address). Michael Bloomberg, George Soros, and the other anti-2A gun control crowd have already begun putting resources together to convince the public and sympathetic lawmakers to restrict or eliminate the availability of the 80% lower receiver. Even with the Trump administration taking the pressure off the Second Amendment, other governmental bodies still have power to act independently. The worst example of this in years just happened in February 2017, when the Fourth Circuit Federal Appeals Court in Virginia overruled its own previous ruling regarding Maryland’s state law banning the AR15 and other similar scary rifles. The court finding was that firearms of this type had no legitimate purpose other than to kill in large numbers and that these “weapons of war” (their words) did not qualify for protection under the Second Amendment. It was not an actual ban per se, but if left standing it would clear the way for an unfriendly federal government issue, an executive order, or a liberal state to pass a law to ban them. Further, in 2016, four states voted on gun control initiatives, and all passed except for Maine’s universal background check measure. Other laws recently passed in California now affect a firearm built there using an 80% receiver through new restrictions going into effect regarding fees, registration, and serialization requirements. Given these pressures, it seems like now is a prudent time to do your research and get to work before it’s too late.

So what are the things that need to be considered before building your own firearm using a legal 80% receiver? You can legally purchase one at this time and perform the final machining operations to make it 100% functional. If done according to ATF guidelines, the 80% receiver is not considered a firearm by any federal or state agency. Since the ATF approved this approach several years ago, manufacturers and sellers have been popping up rapidly. The AR-15 variants have catapulted to capture the lion’s share of the market. Also available are versions for the AK-47, the 1911 pistol, and most recently, an 80% pistol frame designed to be completed using standard Glock pistol components.

In this four-part article series, we will look at the issues surrounding the purchase, completion, and assembly of three very popular 80% platforms:

AR-15 rifle,
1911 Browning-designed pistol, and the
Glock–style pistol, in both full-size and compact versions

There is also a smaller but active AK-47 builder community as well plus a growing AR-10 presence. However, we will focus here on the versions listed above, since they are more widely supported and popular. Other than the specific technical issues, the things that affect the three 80% platforms in this series also generally apply to the other platforms as well.


Understand this up front, I am not a lawyer, so nothing listed here may be considered legal advice of any kind. Your decisions should be made after thoroughly researching the law and published ATF guidelines. At the end of the day, it is your responsibility to confirm which aspects of this apply to you and how they apply. There are some very important distinctions about what the ATF does and does not consider a firearm, including at what moment your 80% hunk-o-plastic or aluminum magically and legally transforms into a firearm. At that moment, it comes under the jurisdiction of multiple government agencies that range from your local LEO to the ATF (depends on your locale). For advice, start with the person or company where you might purchase your 80% components. Realize that they are hoping you buy as much as you can from them, so verify what they tell you. Read the links that are provided here and on their websites. Read the actual laws themselves. I can’t stress enough how important this is. You will learn a great deal here, but at the end of the day it’s completely on you.

What is an 80% firearm?

This is the first and most important issue because an 80% firearm as discussed here is not an actual firearm as purchased. It does not become a firearm until an individual completes the steps needed to transform it into a form that does meet the legal definition of a firearm. To be on the safe side, I consider an 80% component a firearm from the moment the first feature is drilled or milled. The reason I approach it that way is that there is very minimal case law at this time. The only configuration that has been specifically designated by the ATF as “not-a-firearm” is the part you took out of the box that is described in the seller’s Determination Letter (more on that later). In other words, once the 80% component is modified in any way from its “as-received” condition, the government may try at some point to declare that it has become a firearm. This can happen any time it suits their purposes to do so. It would then be up to you to spend the time and money proving that it is not a firearm. Who wants to sign up for that? Just don’t plan to sell your partially finished receiver once you start to machine it. The good news is that at this time, a reasonably competent individual can safely fabricate his or her own 80%-er into a functional lower receiver fairly quickly. Once you’ve gathered the correct additional components, it can also be assembled into a usable firearm without restriction and used as you would any firearm.

What is considered a firearm?

We have to start with a working definition. This is where the ATF website is actually a treasure trove of information. Find out yourself at www.atf.gov. You can find listings of most current federal laws there as well as the ATF regulations that serve to interpret (or some would say, re-write) those laws. Be sure your state laws also allow this kind of build to take place. California is already trying to restrict their large in-state 80% community.

Two of the most important federal statutes that apply are the National Firearms Act (NFA) of 1934 and the Gun Control Act (GCA) of 1968. These two are the source of most of the definitions and restrictions you will have to comply with. That said, here is what the GCA and the NFA calls a firearm:

(A) any weapon (including a starter gun) which will or is designed to or may readily be converted to expel a projectile by the action of an explosive; (B) the frame or receiver of any such weapon; (C) any firearm muffler or firearm silencer; or (D) any destructive device. Such term does not include an antique firearm.

The terms “firearm silencer” and “firearm muffler” mean any device for silencing, muffling, or diminishing the report of a portable firearm, including any combination of parts, designed or redesigned, and intended for use in assembling or fabricating a firearm silencer or firearm muffler, and any part intended only for use in such assembly or fabrication.

The term “make” is defined in the NFA to include manufacturing, putting together, altering, any combination of these, or otherwise producing a firearm.

Once something is legally considered a firearm, it becomes subject to a myriad of restrictions and regulations (yes, infringements) that control its sale, transport, purchase, and use.

"The time for war has not yet come, but it will come and that soon, and when it does come, my advice is to draw the sword and throw away the scabbard." Gen. T.J. Jackson, March 1861

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Learn The Why and How (continued)

The key provision that makes the 80% industry possible is making sure that all the items being purchased and transported are parts and not a firearm. Because once the parts wind up in your hand, you have the right to now “make” a firearm as listed above but only if you can legally own that firearm in your state of residence.

Does this mean I can make my own firearm?

The short answer is “Yes, with conditions attached.” From the ATF website:

An individual may generally make a firearm for personal use. However, individuals engaged in the business of manufacturing firearms for sale or distribution must be licensed by ATF. Additionally, there are certain restrictions on the making of firearms subject to the National Firearms Act.

The second consideration is also critical: (again from the ATF website)

Does an individual need a license to make a firearm for personal use? No, a license is not required to make a firearm solely for personal use. However, a license is required to manufacture firearms for sale or distribution.

So, you can’t sell it, ever. But when does a person need to become licensed? The simple answer is when they are considered “engaged in the business”. The following is once more from the ATF website:

Any person “engaged in the business” as a manufacturer must obtain a license from ATF. The term “engaged in the business” means— (A) as applied to a manufacturer of firearms, a person who devotes time, attention, and labor to manufacturing firearms as a regular course of trade or business with the principal objective of livelihood and profit through the sale or distribution of the firearms manufactured.

It is probably true that if you are simply a hobbyist, collector, sport shooter, or person not “engaged in the business” you would have wide latitude regarding how you built your firearms for your personal use. The reality is that you are in the big gray area. Many believe that the ATF likes it gray because it gives them wide discretion to take appropriate enforcement actions to go after those who they consider “engaged in the business” since that definition is fluid. Clearly, you may not have something as obvious as a corner storefront, website, or other method to sell your home-built plinker.

What about helping a buddy build his or using a drill press at work with the boss’s permission after hours?

Keep in mind that the GCA and NFA already indicate and the ATF has reaffirmed that you may not sell a firearm you make to anyone, ever, and may only pass it on to a family member or surrender it to the government upon your death.

Here are some other questions to consider…

Do I have to fill out any forms or pay to get a tax stamp? This one is a bit trickier. If you are building some type of modified firearm that does not fit the current legal definition of a pistol, rifle, or shotgun, you might have to. Things like short-barreled rifles, handguns with shoulder stocks, fully automatic firearms of any style, sawed-off shotguns, or anything outside the current restriction may have to be registered as an NFA item. See www.atf.gov for the restriction list. You can usually avoid unwanted scrutiny by sticking to the basics and making sure that what you build looks a lot like every AR-15 or 1911 that can be purchased commercially. Also if you make sure it does not have a restricted modification like a suppressor, shortened stock, et cetera, you will generally be on solid ground.
Do I have to mark it or serialize it?

No, but marking it is encouraged by the ATF so they can help identify it if it is lost or stolen. Many people think marking it is a euphemism for having a means to track it. I would mark mine someplace unique and discreet in case it does get lost or stolen.

Is there is a particular part that is actually considered the “firearm”? Yes, and it varies. On a commercial firearm that component is usually either the upper or lower receiver, because that is what must be serialized and tracked through the supply and distribution chain using the serial number assigned by the manufacturer. On the three platforms discussed here, it is the body of the lower receiver or pistol frame that is serialized and recorded. On some firearms, it is actually the upper receiver because the trigger group is housed there.

What is an ATF Determination Letter?

This seems pretty important in my opinion, but use your own judgment. If a manufacturer wants to make an 80% lower receiver available and stay in the good graces of the ATF, they have typically submitted a sample and description of their product to the ATF Firearms Technology Branch, who will review the sample and confirm in writing that what they are making is not a firearm. If it is found to be compliant and not a firearm, the FTB will then issue a letter indicating that only that specific configuration from that manufacturer has been evaluated is not considered a firearm and thus does not have to comply with restrictions as a firearm. This formal notification to the manufacturer is called a Determination Letter and the manufacturers who have one will freely provide it, often right on their website. Curiously, most of the manufacturers listed in this article that I surveyed do not have one specific to their company and seem to be relying instead on the ATF’s general rulings. Consider how important the letter might be to your peace of mind as you make a decision what and where to buy.

Are there any restrictions on using the firearm?

As long as it complies with the ATF-FTB’s interpretation of regulations, it generally meets the same use and handling conditions as any other commercially available firearm except that you can’t sell it to someone else.

Are there any other things to be aware of?

Maybe. For example, here is an interesting restriction that makes little sense but still exists. The first application that a serialized firearm receiver is used for can technically never be changed. In other words, if you initially buy or build an AR-15 lower receiver into an AR-15 pistol, you may never legally recycle it later to build an AR rifle and vice versa. It must always be used in a pistol. Once your receiver is used for a particular firearm configuration, it has to stay that way over its entire life. I’m not sure if it applies to your 80% completed receiver, how it could be enforced or why it even matters, but there it is.

How and where you complete your 80% receiver is critical. It is also important that you realize your 80% receiver must be built solely by you on equipment you own. Without a vote from Congress, ATF Director, B. Todd Jones, released a ruling in 2015 which makes it illegal for a business entity to rent or loan their equipment to a private individual so that person may complete an 80% receiver. It is also prohibited for a private individual to complete an 80% receiver using a friend’s personal equipment. Essentially, this means the only way to complete an 80% lower is working on your own equipment (jig, drill press, drill bits, or CNC machine, et cetera) and finishing it in your own home. Otherwise, the machine shop or your friend could be considered “engaged in the business” of firearm’s manufacture, and without being licensed they could be subject to legal actions. It would be very hard to prove unless you or your friend admitted it. However, law enforcement agencies frequently succeed when they choose to prosecute someone by relying heavily on the testimony of a friend or perhaps an ex-spouse. This person can often be enticed or compelled to testify against you in some way, so keep that in mind and practice good OpSec. Don’t trip yourself up with an accidental admission or social media post that could be used against you. Here is a link to the complete ruling.

How much money can I save?

This may come as a surprise but building one of the popular 80% versions of these handguns or rifles at this time may actually cost more than purchasing a serialized receiver and assembling the other components. Even though they have less manufacturing performed on them, 80% receivers are usually priced higher than their finished, serialized cousins. I expect that will change over time, but it is almost universally true as of this writing.

So why do the build?

That’s a great question. Here are reasons most people give for why they do it:

I can acquire deeper knowledge of the platform and how to gunsmith it.
I want to see if I can do it.
I have a love of the platform.
I want bragging rights / the manly-man or girly-girl factor.
I don’t want the government to know what I have. (BTW, to keep the lowest profile, make sure you are paying with cash, like a money order, have parts shipped to an offsite location, and don’t post it all over your social media.

In Part 3, we will detail the actual process of doing an 80% AR-15 build.

[ 03-09-2017, 11:25 AM: Message edited by: ConSigCor ]

"The time for war has not yet come, but it will come and that soon, and when it does come, my advice is to draw the sword and throw away the scabbard." Gen. T.J. Jackson, March 1861

Posts: 14330 | From: A 059 Btn 16 FF MSC | Registered: Oct 2001  | Report this post to a Moderator
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Cody Wilson's Defense Distributed sells a CNC mill that will machine an 80% AR-15 lower. No prior machining experience is necessary. It's $1200 well spent, especially if you're arming a few people.

Onward and upward,

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Building An 80% Firearm- Part 3, by Tupreco
SurvivalBlog Contributor | March 9, 2017 |

Finishing an AR-15 80% Lower

During the eight years of Obama’s presidency, a record 144 million pre-purchase NICS background checks were performed. This is almost exactly twice the number we saw during eight years of George W. Bush. Whether the numbers return to Bush-era levels under a Trump presidency remains to be seen. Certainly, while a background check is not an actual gun sale, it is widely believed that the numbers do correlate closely to actual gun sales.

This substantial increase in firearms sales also saw a corresponding increase in firearms technology development. Good examples of this include the rise in popularity of the AR-15 rifle with pistol versions and availability of several new calibers; the proliferation of new firearms models; and solid sales growth for items like suppressors and specialty stocks that used to be regarded as curiosities. While Obama’s anti-gun stance clearly polarized the nation, a broader firearms mindset also became evident by increased concealed carry permit issuance and broader concealed carry legislation. Firearms training classes also proliferated as the idea of gun ownership actually attracted many new shooters, and, of course, there was the emergence of the 80% firearms industry.

The 80% firearm idea is simple. It allows an individual to legally purchase an unregulated firearm lower receiver as an incomplete and non-functional receiver blank or casting. The individual can complete the final machining operations themselves using their own equipment to do so. When properly completed, it becomes a functional gun receiver, which can then be assembled into a complete firearm when fitted with the remaining non-regulated parts. When done properly, most are indistinguishable from their commercial counterparts. However, as covered in Parts 1 and 2 of this article series, its use and ownership is limited to the builder and a family member who might inherit it.

First Things First

It is easy to get psyched at the idea of building your own legal “ghost gun”. Hopefully, you can learn something from my experience and mistakes. I wish this kind of input had been available to me before I charged off into uncharted territory. We will examine the options currently available and review a number of tips and tricks to assist you in the completion your own 80% receiver. We will also identify some common potential pitfalls to avoid.

First of all, completing an 80% receiver requires some experience at how to properly use hand and power tools. Those lacking skills here should fine a more experienced friend to mentor them so as to minimize their potential frustration. Also, be aware building an AR-15 using an 80% lower is really a project with two distinct phases. Phase 1 is taking your 80% blank and completing the necessary steps to make it functional. Phase 2 is to use that completed lower, now at 100%, by then assembling the rest of the parts properly to produce and test the completed firearm. I strongly recommend participating in the assembly of at least one conventional AR-15 build using a factory-built or other known-good lower receiver before tackling one with your 80%ers. This way you will experience what a normal AR-15 build feels like, so you will have some sense of whether the lower you just finished machining is being stubborn, if it is just a normal assembly challenge, or if there is another defective component. That said, let’s begin.

Picking a Material and Finish

Before your order a receiver, jig, and tools, you need to decide whether you want a receiver made of aluminum (which is harder to machine) or polymer (which is easy to machine). If choosing polymer, will you choose an injection molded polymer to machine or mold your own using a two-part polymer mold pour? Review the options carefully because once you build one, you will own it for a lifetime.

If choosing aluminum, there are generally two ways to buy an 80% aluminum receiver; they come raw or anodized. A raw unfinished receiver should be later finished to protect it from corrosion and scuffing. The best for finishing raw aluminum are the hard-cure coatings such as Gun Kote, Cerakote, or Dura Coat. Spray paint will work but may need frequent touchup. The second alternative is to buy it already hard anodized. An anodized finish is an electrolytic plating operation that significantly and uniformly forms a durable aluminum oxide finish that protects the surface. The machining operations performed while completing the receiver will leave raw aluminum exposed where it was machined but corrosion coating those areas isn’t as critical.

If you opt for a polymer lower, no additional finishing will likely be needed. Black is the most popular but many non-black options also exist. Color can be introduced by molding it using a color polymer feedstock or using a hard-cure coating over a black receiver after completion. I personally choose an anodized lower for my first build because that’s how every high-end AR-15 I saw was built. I used a polymer lower for a second build because my goal was to build a real AR-15 rifle chambered in .22 lr that weighed less than 4 lbs.



Here’s a chart that shows the comparison:


Choosing a Supplier

After selecting the type of material and finish, you will have to review what each maker has to offer and decide where to buy. Be sure to review what type of jig / tool combination they have available and how much support they offer. One final note about selecting a company’s lower system is whether they have gone to the trouble of getting their own ATF Determination Letter. This letter certifies that their product is an ATF-approved true 80% lower. Here’s one reason why it might someday matter. A few years ago, one firm in the early days of 80% receiver– Ares Armor in southern California– was raided by the ATF and temporarily shut down because they built their 80% lower with a different color piece of plastic permanently molded at the exact location of the fire-control cavity. Buyers would then simply Dremel out or mill away the different-colored plastic from that area and drill a few more holes to complete their lower. It was a clever approach, but the ATF held that by adding the color in the shape of the cavity to be removed, Ares Armor was illegally facilitating the manufacture of a firearm by its actions. Essentially they were now judged to be selling a firearm, not an 80% lower. A lower from a maker without a Determination Letter may be just fine, but I think it is better to be safe than sorry. Oh, the ATF also confiscated Ares Armor’s entire 80% receiver customer list along with Ares Armor’s other business records.

Choose your lower and you’re on your way. I compiled a pretty complete list of most of the available sources I could find and whether they offer matching jigs and tools. I also tried to find out whether they have an ATF Determination Letter. I made no attempt to compare them, other than a few comments. No claims are made for the completeness or accuracy of the list. I have no involvement, recommendations, or worries relating to any of them, except for what I have already discussed.


Jigs and Cutting Tools

Most manufacturers also offer a jig suited for their lower with a tool set to match. If possible, consider getting your jig, cutting tools, and lower from the same source. They are more likely to work together, which will give you a better chance at success. The best jigs have replaceable drill bushings, but this is not critical. I like drill bushings because they are replaceable and reduce wear from repeated use. This means that hole placement will stay more precise over time. The best jig makers also have both written and video instructions. I would definitely avoid the peel-and-stick label jig templates that some vendors offer as an alternative to a jig to guide your work. A friend was halfway through a milling cut when his label template wrapped itself around the spinning cutter. It shredded his confidence right along with the template. Aluminum jig came to the rescue.

Doing the 80% Machining

– For drilling the hammer pin, trigger pin, safety selector hole, and other holes needed, a good electric hand drill or drill press will do as long as you are careful. Lube while drilling or milling helps also. Milling out the fire control pocket will be the most challenging part. It is the operation where people make the most mistakes and break the most tools. That’s because people are less familiar with milling, which is different than simple drilling. In milling, the spinning cutter is stationary and you feed the workpiece into the cutter. Drilling is done on a stationary workpiece and the spinning bit is fed into the workpiece. Also, in milling you are often taking material off of two surfaces at once, so it is easier to slip. Personally, a benchtop drill press and a manual $49 Harbor Freight cross-slide milling vise is the minimum I am comfortable with. Like you, I’ve had projects ruined by power tool bit slippage. Make sure you properly clamp the workpiece, control the feed rate between bit and workpiece, and prepare to stop quickly. There are videos all over YouTube of people using these methods successfully. Good luck and be careful!

Plan Ahead

Do your homework and dry fit parts and jigs together to make sure they fit; then, reread everything and watch the video one more time! YouTube and Vimeo are loaded with some good and bad examples of people completing their lower. Watch a few. It’s an inexpensive way to learn from the mistakes of others.


Some Random Considerations

RPM and Feed Rate – Watch your spindle speeds; you need a minimum speed to cut properly, and too fast will burn the bit and workpiece as well as melt the polymer. I’ve seen several recommendations to stay around 600-800 RPM, but YMMV. Keep a can of cutting oil near and use it frequently, especially on the harder aluminum grades used in AR-15 lowers. Remember that WD40 is not a lubricant. Also, watch your feed rates (how much and how fast you push cutter into the workpiece). More passes with less removed per pass is better than too much. Bit breakage is to be expected, and I don’t recommend starting a build without a spare milling cutter.
Mistake Proofing – Preventing mistakes is way easier than trying to fix them. Here are some suggestions:
Cover exposed surfaces with blue painters tape to prevent scratching.
Use screw-on drill collars to keep drilled hole depths from going too deep.
Use the tool stops on your machine or clamp on small blocks of wood to guide tool movement and limit slippage and overtravel.
Repairing mistakes – Fortunately, if you still make a mistake, there are some limited ways to reverse the damage. JB Weld two-part epoxies are a godsend here. Stick to the standard JB Weld and the JB Aircraft weld. It can be machined like aluminum or polymer, once it sets. Avoid the 15 min. Kwik Weld; it’s not as strong. Rapid Fix is a 2-part system that includes cyanoacrylate liquid and a fine plastic powder. It makes a fast-drying slurry that can actually fill holes with multiple applications and can be machined and painted later.

Should I serialize it?

Putting permanent identifying marks on your lower is not legally required but strongly recommended by the ATF. You may want to consider it for two good reasons:

It will allow you to identify and recover your firearm if it is stolen, and
Commercial firearms made after 1968 must have a serial number affixed by the manufacturer. Removing the serial number or owning a gun with the number removed are both felonies. Older guns that never had one are okay. However, if a local LEO decides that your unmarked but legal ghost gun may really be evidence of a felonious serial number “file off”, the burden of proof will be on you to prove it doesn’t have one or need one. That said, many people avoid the problem by using a short numeric code on the area normally covered by the grip using an inexpensive metal stamp set or engraver. Since your unique number is only known by you and is nowhere “in the system”, there is really not much downside.

You followed all the tips, and now it’s done!

Now that you have a functioning receiver, it’s time for the rest of the build. Since the focus of this series is the 80% receiver, I am going to leave the balance of your AR-15 build up to you. There’s a ton of good info online about doing the remainder of a build. I hope this detailed look at the possibilities of completing your own Ghost Gun lower has been worth your time.

Next up: Building an 80% Firearm– Part 4, 80% versions of 1911 and Glock-type pistols.

"The time for war has not yet come, but it will come and that soon, and when it does come, my advice is to draw the sword and throw away the scabbard." Gen. T.J. Jackson, March 1861

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Building an 80% Firearm-
Part 4, by Tupreco

Building 80% 1911 and Glock Pistols

In Part 3 of this series, we took a detailed look at selecting and completing an 80% AR-15 lower receiver. Whether or not you choose to build an AR-15 ghost gun, you may be interested to know that there are also 80% pistol frames and build kits out there to make your own ghost pistol as well. It’s a great challenge and very satisfying to complete one successfully. First, we will look at the legendary John Browning-designed 1911 version.

Your 1911 Ghost Gun

Trying to explain the popularity of the 1911 .45 ACP pistol is like trying to tell someone why you love your Harley Davidson motorcycle. It goes beyond simple functionality, often being described as something that just feels right. A friend, who is a fanatic for both his 1911 and his Harley, once told me that while neither of them could be called the best versions among their competitors, they both fulfill their mission in a way that feels uniquely American. They are both solid performers, each with its own rich history and back story. So it’s no surprise that an opportunity to build your own version of a handgun with such a storied tradition would be popular. There’s no question about it; the 1911 is the most popular 80% pistol build as of this writing.


Do the 1911 project for the privacy factor, bragging rights, and love of the platform because it’s a bit challenging, and it almost surely will cost you more than a good quality commercial 1911 from a mainstream manufacturer, like Springfield or Ruger. There are lots of YouTube videos are out there that show the success and challenges of doing this build. Choose wisely, and work carefully.

Material Options

Here is the list of readily available frame material choices for your project, from the most expensive to the least expensive. Some vendors offer quantity purchasing discounts as well.

416 Stainless steel

4140 Cold Rolled Steel

7075 forged aluminum

Variations and Calibers

There is no caliber-specific difference when finishing your 80% 1911 frame. Primarily, the caliber is determined by your choice of slide, barrel, and magazine. Depending on the caliber, there may be a few tweaks necessary during the remainder of the build. The original and venerable .45 ACP is overwhelmingly the caliber of choice for most builders. If you need to ask why, then you should probably just move along because there’s nothing more for you to see here. However, other calibers do have their supporters. A successful .45 ACP build can typically accept 22lr conversion slides and magazines. There is also a high-performance .460 Rowland kit available, and some 9mm versions are also starting to appear as well.

Parts Availability

The 1911 has been a mil-spec firearm for many years. Even though it is retired, it enjoys the resulting benefit of component standardization that helps assure a steady supply of parts for the 80% builder and lots of modifications. Combine that fact with a fanatic base of 1911-lovers and you can rest assured that there will be a robust aftermarket for this platform for years to come. However, there are still about 40 additional parts you will need after completing the receiver/frame, so this still tends to be an expensive project. Some suppliers are starting to offer packaged 80% completion kits, so shop around.

Major Suppliers

Currently I have been able to identify six online sources that appear to have their own unique source for 80% receivers. The first three seem to currently be the most popular if you consider the many videos and forum postings debating their relative merits as evidence of their popularity. They all sell frames as well as work holder jigs to simplify completion. You might also see a limited selection of their frames listed for sale by major distributors, such as Brownell’s and Midway.


Here’s a picture of a complete kit from Tactical Machining showing the 80% 1911 frame, jig, and completion kit. [fig3]

Budget Realities

Prices for a plain 80% bare receiver will start at about $159–$300. Expect to pay between $600 and $1100 for a complete kit with all parts. The jig will add about an additional $90 for just the work holder and up to $175 for a complete setup with all of the needed cutting tools. While you could produce multiple finished receivers on the same jigs, the reality is that these smaller cutting tools are very prone to breakage, so be prepared to spend more money.

Parts tip #1– I bought a Para Ordnance 1911 with a gouged-up frame at a police auction that was sold in parts-only condition for $150 bucks. It was a modest beginning, but it fit the budget and all the parts swapped straight across. My total build cost for a stainless frame, including a DuraKote job on the slide to match, was about $450 with all bragging rights intact.

Parts tip #2 – Several eBay sellers have complete 1911 parts kits less the lower receiver for sale starting at about $225. That’s not too shabby.

The 20% Required To Complete It

With the 1911 you will be better off with an actual milling machine, better measuring equipment, and some machining skills for a successful outcome. If you are planning to try it with a Harbor Freight drill press and a Dremel, it will be a challenge, so plan accordingly. Here’s generally what will need to be done to complete Phase 1:

Milling extra material from top of frame and slide rails
Drilling hammer and sear pin holes
Milling out barrel seat

The same rules and suggestions that were discussed during Part 3 – Finishing the AR-15 Lower of this series apply here as well. There is more milling setup on the 1911 frame than with an AR-15, and the frame material is steel instead of aluminum. This translates into more opportunity for mistakes, so be careful and use the old adage “Measure twice then cut once.“ Once complete, you can begin the second phase to assemble everything together. The other suggestion made in Part 3 of this series is to become thoroughly familiar with the assembly and disassembly of the 1911 before tackling this project. Having someone verify your work as you go will help you build confidence. When finished, you can use any suitable 1911 mag and ammo. Also, make sure you match the lower with the proper slide and barrel length.

The 80% “Not-a-Glock” Glock

Polymer 80 was one of the early arrivals to the 80% AR-15 industry. They have been offering AR-15 kits for several years and now have an 80% polymer AR-10 lower system as well. They also recently introduced a newcomer to the 80% pistol build community that shares all of the working parts and most of the DNA of a Gen 3 three-pin Glock handgun. Their P940 Spectre frame family has opened the world of the Glock-type clone to 80% builders. The full-sized P940 follows the Glock 17/22 pattern and the P940C tracks with the Gen 3 Glock 19/23 compacts. One person jokingly referred to it as the “Not-a-Glock” pistol line. They are available in about five colors.

The current form factor of the Glock polymer pistol is protected by design patents and other intellectual property provisions, so an alternate design was required. Polymer 80 designers did their homework and came up with an ingenious solution. They managed to leverage the popularity of the Glock pistol into an 80% ghost gun frame and offer it with jig and tooling as a very reasonably-priced $160 package. As you can see in the picture below, they also found a way to update the design that replaces clunky Glock look with more “1911-style” grip characteristics and trigger guard so the result is a very functional combination of both a Glock and a 1911 while looking like neither one. [fig4]

The barrel, slide, and innards used to complete the build require that you use ultra-reliable Glock parts or clones. It’s a pretty ingenious combination and sales have been brisk.

My P940 Build

Let me say up front that I can’t recommend doing this build unless you are familiar with how to completely disassemble and reassemble a Glock Gen 3 pistol or have access to someone who is familiar and who won’t mind your frequent questions. You will understand why as you read on.

I purchased my black P940 from Brownells on a $99 special and completed it in less than three hours. That included all the hand filing and fitting needed to make sure the slide fit and operated smoothly yet snugly. I found it to be doable with my bench top drill press, a dremel, a number of small files, and a solid measure of deliberation. The only item of note is that the process of milling the slide rails deep enough to be functional required cutting deeply into the red jig, which probably rendered it unusable for future completions. The cutting tools were all intact and still sharp.

Lone Wolf Distributors had the foresight to offer a complete 80% lower parts kit for a reasonable $81 that already included the 3.5 lb trigger connector I wanted. I ordered the 9 mm version, and it arrived quickly. It was mostly Glock OEM parts with a few Lone Wolf parts included. Everything fit perfectly. It helped to have a Glock 17 handy because it does not include any instructions. Check with other distributors like the Glock Store and Glockmeister as they are getting on the Polymer 80 band wagon as well.

Summary of the P940 – This project, like the 1911, essentially requires that you do a lot of work to complete the lower, then procure a parts set for a complete Glock without the frame. Next you assemble those parts to your P940 lower and confirm it is safe before firing. Here you are again with another 80% pistol build that costs about 20% more than buying the comparable quality commercial version. Here’s the breakdown- The best price I have seen for all of the other required parts as a kit has been on eBay where the cheapest used Glock 17 or 22 complete kit including slide, barrel, and no mags has been $450 shipped. Add about $75 if you want new parts. Now add that to the typical street price of the P940 kit at $120 and $40 more for two mags. You are now at $610 out the door. This for the P940 build comparable to the Glock 17/22 pistol that you can buy brand new for $499 all day long. I just looked on Armslist and saw that I could purchase a used/like new Glock 17 with no background check offered private party in my area for $450.

So just like the 1911, do not do this build because you think it will save money. Do it for the bragging rights, the experience, the privacy, and the fact that you now can have a great combination of Glock reliability and 1911 grip characteristics rolled into one firearm. It is interesting to me that the ultra-reliable Glock went together using a total of only 18 parts while the 1911 required more than 40. I’m just saying…


I love building these special projects, and I am happy to share my experience. I have a fondness for Glocks and wanted to give the P940 a try because I have owned an Advantage Arms .22lr Glock 17 upper conversion kit for several years. I paid $200 for it several years ago with three mags, and it is great to shoot with. As mentioned earlier, I built my P940 80% lower complete for $180. Now using my $200 AA slide and barrel I have the equivalent of a dedicated Glock 17 chambered in .22lr with two mags for $380. I’ll go with that. Good luck with yours.

"The time for war has not yet come, but it will come and that soon, and when it does come, my advice is to draw the sword and throw away the scabbard." Gen. T.J. Jackson, March 1861

Posts: 14330 | From: A 059 Btn 16 FF MSC | Registered: Oct 2001  | Report this post to a Moderator

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