People in the United States have been making their own firearms for as long as guns have existed. The Second Amendment right to own and carry firearms includes the right to fashion homemade firearms.
Even in an era of heavier federal and state gun restrictions, most homemade guns (also called "self-assembled firearms" or "privately made firearms") are legal. Here's an overview of how homemade guns are regulated.
The United States Supreme Court has held that ordinary, law-abiding citizens have a Second Amendment right to keep a gun at home for self-defense and to carry a handgun in public for self-protection. (District of Columbia v. Heller, 554 U.S. 570 (2008); New York State Rifle & Pistol Association v. Bruen, 597 U.S. __ (2022).)
However, the Court has also acknowledged that Second Amendment rights aren't unlimited and that lawmakers can still impose regulations, such as forbidding some people from possessing them (felons, for example); prohibiting them in places such as schools and government buildings; and imposing conditions and qualifications on their sale, licensing, and regulation.
The federal Gun Control Act of 1968 (GCA) requires, among other things, that people "engaged in the business" of dealing firearms get a license from the federal government called a Federal Firearms License (FLL). The GCA makes it illegal for a person without an FLL to make a firearm for sale or distribution. In addition, the law requires firearms dealers to perform background checks on people who want to buy a gun and to maintain records of all gun sales. (18 U.S.C. § 921(a)(21)(C)(2023); 18 U.S.C § 922(t) (2023); 18 U.S.C. § 923 (2023).)
However, nothing in the GCA prohibits individuals from making guns for their own personal use. A person without an FLL may make a firearm for personal use without undergoing a background check, as long as the person isn't otherwise prohibited from possessing firearms. A homemade gun doesn't have to be registered unless state or local law requires registration. (18 U.S.C. § 922(d) (2023).
Although the federal government hasn't regulated most homemade guns, state governments and local municipalities (cities, towns, and unincorporated areas) can regulate them as long as the regulations don't conflict with federal law. A growing number of states, like California and Colorado, have passed laws regulating homemade guns. Several cities have also imposed their own regulations, including New York, Los Angeles, San Francisco, and Denver.
People convicted of felonies, as well as some kinds of misdemeanors, can't legally possess a gun—homemade or otherwise. Federal law prohibits gun possession by anyone convicted of a felony or domestic violence misdemeanor. (18 U.S.C. § 922(g) (2022)
Some states have additional prohibitions. California, for example, also forbids gun possession by people who know they have a felony arrest warrant, and people convicted of certain misdemeanors in the past 10 years (including simple assault or battery, and domestic violence crimes). (Cal. Penal Code §§ 29800, 29805 (2023).)
A person's criminal history isn't the only factor that can lead to losing the right to possess a gun. Federal law prohibits gun ownership by people who are subject to domestic violence restraining orders, illegal drug users, mentally ill (if determined by a judge), immigrants who have entered the country unlawfully, dishonorably discharged former members of the military, or fugitives from justice (people who are on the run from the law).(18 U.S.C. § 922(g) (2023).)
States often have their own laws prohibiting gun ownership. For example, California bans gun possession by people subject to various types of temporary restraining and protective orders, including not only domestic violence protective orders, but anti-harassment restraining orders, and gun violence restraining orders under California's "red flag law." (Cal. Penal Code §§ 18150, 29825 (2022).)
While it's always been legal for people to make homemade guns, it hasn't always been easy. A gun is a highly machined piece of equipment, dependent on precise specifications and materials. In the past, homemade guns were often crude because individuals lacked the equipment and know-how necessary to make sophisticated weapons. However, modern technology has addressed many of these challenges, by offering "partial receivers" and the ability to make guns using 3D printing.
A ghost gun is a firearm that is privately assembled and untraceable. Ghost guns are often made through kits sold online or at gun shows that contain all of the parts and sometimes even the necessary equipment to build the firearm at home. Increasingly, ghost guns can also be 3D-printed. Anyone can purchase a ghost gun kit or download the blueprint for a 3D ghost gun and the ghost gun itself doesn't have a serial number.
A gun's "frame" or "receiver" is the part of the firearm that houses the mechanical components and projects the bullet. The Gun Control Act (GCA) includes finished frames and receivers in its definition of regulated firearms. A person buying a finished frame or receiver would have to get it from a licensed firearms dealer, pass a background check, and register the firearm. Finished frames and receivers have serial numbers that can be used to trace the frame or receiver to the registered owner. (18 U.S.C. 921(a)(3) (2023).)
A person interested in avoiding a background check and gun registration can instead buy an unfinished frame or receiver to make a ghost gun.
An unfinished frame or receiver (also called an 80%) is a partially completed receiver that requires additional tooling to be fully completed. A key difference between this kind of receiver and a finished receiver is that it hasn't historically been treated like a firearm and regulated by the GCA. The lack of regulation also means that unfinished receivers have no serial numbers.
Unfinished receivers are legal to sell in most states and are widely available online and at gun shows. According to the Washington Post, the process of converting an unfinished receiver into a firearm is relatively simple and can take one to seven hours depending on your skill level. Unfinished receivers have no serial number and can be sold without a background check, which makes them attractive to people who can't buy a firearm legally or want a gun that can't be traced back to its owner.
In August 2022, the Biden Administration enacted a new ATF rule in an attempt to crack down on ghost guns. The new rule clarified the definition of a firearm under federal law, requiring serial numbers and background checks before unfinished frames or receivers can be sold. But Gun Owners of America (GOA) and others quickly challenged the rule in court. In July 2023, U.S. District Court Judge Reed O'Connor vacated the new ATF rule, finding that it exceeded the federal government's authority under the GCA. (VanDerStok v. Garland, 4:22-cv-00691 (N.D. Tex.) (2023).) The case is headed to the Fifth Circuit Court of Appeals. The U.S. Supreme Court decided to allow the federal rule to stay in effect (stayed the lower court's ban) while the case makes its way through the appellate courts.
A growing number of states regulate ghost guns and other homemade guns. California, for example, requires any person who possesses, manufactures, or assembles firearms in the state to apply to the state Department of Justice for a unique serial number. Violations can be charged as misdemeanors. (Calif. Penal Code § 29180 (2023).) Guns rights groups are challenging these regulations in some states, such as Colorado.
As previously noted, the federal Gun Control Act of 1968 (GCA) requires people "engaged in the business" of dealing firearms to get a license from the federal government called a Federal Firearms License (FLL). Nothing in the GCA prohibits individuals from making guns for their own personal use, but not for sale or distribution. A person who makes a gun for the purpose of selling it would have to get an FLL.
Some people argue that federal law allows an unlicensed person to sell, give away, or otherwise transfer a homemade firearm to another resident of their state if the gun was originally intended for personal use. Determining whether a gun was originally intended for personal use involves looking at many factors, including:
The safest way to sell anyone a homemade gun is to be licensed or have someone with an FLL facilitate the private sale. You typically must be licensed or an FFL to transfer a firearm to a resident of another state. A licensed firearm dealer will conduct a background check on an individual seeking to buy or receive a firearm and complete the necessary paperwork. (18 U.S.C § 922 (2023).) The ATF maintains a list of FFls in each state.
Remember, state and local governments may have their own laws regulating the sale and transfer of homemade firearms. Some states, like California, prohibit the sale or transfer of nearly all self-made or self-assembled guns. (Calif. Penal Code § 29180 (2023).) Talk to a legal expert familiar with local, state, and federal gun laws before you transfer a homemade gun.
Anytime you're facing a charge for unlawful gun possession, or want to know whether a state's laws allow you to possess a particular kind of gun, you should talk to an experienced criminal defense lawyer in your area. Violations of gun laws can result in years in prison. An experienced attorney can advise you about your rights and ensure you're protected.