This guide will serve as your ultimate source for the 1911 handgun. We’ll explain the history of America’s favorite pistol, its configuration and variants, and we’ll even example how to legally build your own gun at home using an 80% 1911 build kit.
DISCLAIMER: We’re not lawyers, and nothing in this guide should be misconstrued as legal counsel. This guide is for educational and entertainment purposes only. Consult with an attorney before building a firearm in your state.
The History of The 1911
The semiautomatic, .45 ACP-chambered Model 1911 pistol was designed and introduced by legendary gun maker John Browning. The aptly-named pistol was introduced the year of its name, beating out the Luger pistol (chambered in 9x19mm Parabellum) for its initial military contract. The M1911 has continuously been in service ever since, making it one of the oldest original firearm designs still employed by modern militaries today.
Browning’s other notable creations include the famed M1917 and M1919 machineguns, and the Browning Hi-Power pistol. But the M1911 remains his greatest creation with over 2.7 million units produced and still in service in 20 different countries.
M1911 Parts Diagram
This diagram illustrates the 1911’s design, which has largely remained the same to this day. Modern variants are available with new springs and triggers, but the gun’s basic operation, parts, and overall dimensions are the same as they were over 100 years ago.
The 1911 uses a locked breech recoil system to cycle rounds. As a round is fired, pressure builds inside the chamber and barrel (#1) until a sufficient amount “unlocks” the breech, forcing the slide (#40) backwards and ejecting the spent shell casing with the extractor (#8). A recoil spring (#32) slams the slide forward, chambering another round.
Modern 1911 Variants and Frames
Today, the 1911 is available in different configurations: Government (full-size), Commander (compact), and Officer (sub-compact). Each variant uses the same types of components and each is configured the same way. External and internal dimensions will vary, so not all parts are interchangeable.
Government 1911 (5″ Frame)
The Government 1911 is considered the “O.G.” shooter. It’s John Browning’s original design, sporting a 5″ steel frame (often called a Government frame) and built using the same parts and specifications. This is the most popular type of 1911 sold and built in the U.S. Pictured to the left is an 80% 1911 frame, an aluminum frame blank that can be used to build your own handgun at home. We’ll touch on all that later.
The full-size 1911 carries 7+1 rounds and is considered a tank by most shooters. It weighs in at a whopping 40 ounces when empty (2.5 pounds), and measures 8.25″ in overall length. All that size and weight is considered an advantage: The Government model is sufficiently accurate to 100 meters and potentially beyond, and it absorbs recoil efficiently.
Commander 1911 (4.25″ Frame)
The Commander 1911 was introduced by Colt in 1950 as a service pistol for – you guessed it – U.S. Military officers. The Commander sports a slightly smaller frame that is made of steel or lightweight aluminum. It’s frame and barrel are slightly shorter (4.25″) and with configurations available in 9mm, .38 Super, and .45 ACP. The Commander is the product of the U.S. government favoring a lighter, smaller replacement for the Government shooter. The new Commander had to weigh less than 26 ounces (1.65 pounds), so it ditched the steel frame.
The Commander’s smaller length (7.5″ total) and lighter weight make it a popular carry piece among shooters. Sacrificing just 0.75″ of barrel length, the Commander yields plenty of accuracy under 100 meters. Because vertical length is the same, the Commander also sports a 7+1 capacity. The Commander and Government 1911 models share mostly the same parts save for the barrel, barrel lug, and slide. Some shooters have found guide rods and recoil springs are interchangeable on certain models.
Officer 1911 (3″ to 4″ Frame)
The Officer 1911 is a departure from the original design. These super-compact shooters have new parts and revised dimensions to accommodate the 1911’s functionality and calibers. The frame on an Officer 1911 is vertically shorter and has a lower magazine capacity of 6+1. Most Officer frames measure 3.5″, with variations ranging from 3″ to 4″. Most parts on an Officer 1911 can not be swapped out with a Commander or Government model. Sporting a steel frame, most Officer models weigh 28 ounces empty and measure 7″ in total length.
To make the Officer work, the barrel had to ditch a traditional barrel bushing. To accommodate the shorter slide, the barrel is also belled and contacts the slide itself. One locking lug is removed to allow the barrel to recoil back more toward the rear of the frame, to allow rounds to cycle reliably with the shorter slide rails.
What is an 80% 1911 frame?
The 80% 1911 is a firearm frame blank that is 80% complete, but not yet functional. The blank is inoperable and cannot be made operable without cutting and drilling it. It is therefore not considered a firearm under the Gun Control Act of 1968. The ATF can only define and regulate firearms. They don’t regulate receiver blanks, frame blanks, or inoperable stuff. In their eyes, the 1911 frame blank is no different than a piece of raw aluminum you bought at a hardware store.
Building a gun: The legal stuff
First thing’s first: A lot of people ask, “can I build a gun at home?” The Bureau of Alcohol, Tobacco, and Firearms (ATF) has this say to on the subject:
“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. The law prohibits a person from assembling a non–sporting semiautomatic rifle or shotgun from 10 or more imported parts, as well as firearms that cannot be detected by metal detectors or x–ray machines. In addition, the making of an NFA firearm requires a tax payment and advance approval by ATF.”
[18 U.S.C. 922(o), (p) and (r); 26 U.S.C. 5822; 27 CFR 478.39, 479.62 and 479.105]
The 1911 is not:
- A shotgun
- An NFA gun
- A non-sporting semiautomatic rifle
- A gun built with 10 or more imported parts
- A gun that can’t be detected by metal detectors or X-rays
We’re not building our 1911 to sell it, and we have no intentions of doing so. So, we’re in the clear as far as Federal law is concerned.
Some states have special restrictions against building guns at home, especially handguns. California, for example, only allows specific handgun makes and models that have been tested for certain safety requirements to be legally owned in the state. Unfortunately, that excludes the 1911 frame blank. Check your local and state laws before building. Moving on, let’s look what what parts we need:
Finishing a Frame Blank: Parts Needed
Here’s what you’ll need to build your gun from scratch. The first two components of the project, the frame blank and parts kit, are caliber- and frame-specific and must correspond with each other.
For example, if you want to build a classic, G.I.-style gun chambered in .45 APC, you’ll need a 5” Government frame blank and 5” Government Parts Kit. The same rules apply for Commander and Officer models, as well as variants chambered in 9mm or .38.
“Are these 80% 1911s compatible with retail parts?”
Yes. If you wanted, you could just buy a frame and jig, complete the frame, and then buy all the parts you’d need from wherever else. But the parts kits, barrels, and slides included with the frame blanks are specifically machined to ensure tolerances are perfect for final assembly. If this is your first time owning or building a 1911, we recommend purchasing the parts included with the full build kit.
Frame blank vs. Retail frame
Speaking of aluminum, the 1911’s 80% frame is not made out of steel. Instead, these blanks are made from forged, mil-spec aluminum. This is no different than using a typical 80% lower used to build an AR-15. This aluminum construction provides some big advantages, the biggest being weight savings. The aluminum frame weighs around 60% less than a store-bought, steel frame. That’s a huge reduction in weight, making the finished gun more comfortable and ergonomic without sacrificing reliability.
And since the frame blank isn’t a firearm, it can be bought, sold, and shipped to you without having to deal with the ATF or an FFL. Nothing else you’ll buy for this project is considered a firearm either, including the parts kit and jig.
How to finish a 1911 80 frame
Now that we’ve cleared up the legal stuff and figured what you what you need for the build, let’s get started! These instructions are to be used only with the Phantom 1911 Jig by Stealth Arms. Other 1911 jigs may work differently:
Step 1: Insert 1911 frame into Phantom Jig
The Phantom Jig secures your frame blank using two provided dowel pins and one Allen-head set screw. Seat the dowel pins into one of the two plates as pictured. Let your frame slide onto the dowel pins and then sandwich the frame using the other plate and set screw.
Step 2: Drill the hammer and sear pin holes
Rest your frame and jig on its side. Secure the larger drill bit (pictured #22) into your drill and drill half-way through the frame to begin making the hammer pin hole. Repeat drilling of the sear pin hole using the smaller drill bit (pictured #35). Then flip the frame and jig and finish drilling on the opposite side.
WARNING: Don’t attempt to drill all the way through the frame on one side. Your drill bits will hit the surface underneath the jig and cause your drill to “walk”, damaging your frame and work bench.
Step 3: Set up the cutting car
After drilling both holes, you’ll move on to the cutting car. This is the manual cutter used to finish the slide rails and barrel seat. The car already has the slide rail and barrel seat cutting blades installed, but they need to set before you begin cutting.
Loosen the Allen-head set screw securing the slide rail cutter (pictured), and carefully push the blade up into the car so the blade’s edge is slightly inside the bottom of the opening. Re-tighten the screw.
Next, thread the cutting handle and adjustment knob atop the car (like shown). You’re now ready to find your starting point for cutting.
Step 4: Set up the jig for cutting
Place the provided spacer block inside the center of the slide rail slot on the guide plate (pictured).
Then, secure your frame and jig in a tabletop vise as shown.
Step 5: Set the initial cutting depth
Once the jig and frame are secured, grab the included machining lubricant and apply some to the frame, inside the slide rail slot on the guide plate. Next, rest the cutting car atop the frame, with the cutting blade resting inside the slide rail guide slot.
Gently move the cutting car back and forth atop the frame while turning the adjustment knob clockwise. This will begin bringing the cutting blade in contact with the frame. Continue rotating the knob until the blade contacts the frame. This is your initial cutting depth.
Once you’ve found the initial depth, grab a marker and mark where the adjustment knob is in relation to the jig (pictured).
Step 6: Measuring slide rail cutting depth
There are notches surrounding the adjustment knob. These notches represent 1/10th of a full revolution of the knob. The knob must be rotated 19 times (1.9 complete revolutions) to achieve the desired cutting depth of 0.61”.
Step 7: Cut the slide rails
Once you’ve found and marked the starting position, begin cutting the slide rails by pushing the car forward across the frame. Make 3 to 4 passes before rotating the adjustment knob one notch. After making a forward cutting pass, it’s a good idea to lift slightly on the cutting car in order to bring it back to you for the next pass.
This will prevent the back of the blade from dragging along the frame and dulling. Be sure to clean out metal scraps and debris while you cut. It’s also important to occasionally apply machining lubricant/oil while you cut.
Repeat for the opposite side.
Step 8: Set up the jig for the barrel seat cut
Once both slide rails have been cut to 0.061”, disassemble the frame and jig and re-position the dowels pins in the side plate as shown. Re-secure the frame and jig atop the guide pins, and re-seat the jig with the provided set screw (pictured).
Step 9: Secure the jig for cutting again
Secure the frame and jig vertically in a tabletop vise, like shown. The barrel end of the frame should face toward you.
Step 10: Set up the cutting car for the barrel seat
Loosen the adjustment knob and handle on the cutting car. Re-position both on the left-hand side of the car as shown. Repeat step 5 to find the initial barrel seat cutting depth.
Step 11: Cut the barrel seat
Repeat step 7 and cut the barrel seat to a depth of 0.077”. This is achieved by making 2.4 complete rotations of the adjustment knob, or 24 notches. Mark the starting position and make 3 to 4 passes, lifting and lubricating as needed until cutting is complete.
Your 80% 1911 frame is complete!
Once you’ve finished cutting the barrel seat, you’ll be the proud owner of a real, functional 1911 frame. At this point, you’re now the owner of a firearm in the eyes of the ATF. And now, you must observe all applicable gun laws. But now comes the fun part: Finishing your 1911 and hitting the range. All you need to do now is install your 1911’s parts kit, which includes the barrel and slide.
Like we said, your completed 80% 1911 frame functions exactly like a retail or store-bought 1911. The parts kit installation is just like any other 1911 you’ve put your hands on.
If you’re not familiar with the installation procedures, there are plenty of resources online (trying to provide every step and photograph in this guide would be unfeasible). One of our customers, Sterling Archer, created a wonderfully paced, easy-to-follow instructional video. Check it out here if you need detailed instructions to complete your installation.
Equipped with our guide, you should be able to master your 1911 build and create the perfect G.I. or compact shooter. If you have any questions about purchasing or finishing a frame blank, using the Stealth Arms jig, or assembling your parts kit, just give us a call or email us. We build our own guns, too! We’re glad to help.