[6] However, the U.S. has appealed to the Fifth Circuit,[6] and O'Connor's injunction was stayed by the U.S. Supreme Court, allowing the rule to go into effect pending further proceedings.
[14][15] Certain companies in the 1990s began to sell receiver kits that could include drill bits, stencils, or jigs to aid the finishing process.
[21] The Intelligence Division of the New York City Police Department has published a survey and compendium of homemade firearm types.
"[26] Wintemute wrote that the relative inexpensiveness of 3D-printing equipment could facilitate the growths of arsenals held by violent extremist organizations.
[25] Noted crimes in which homemade firearms were used include the shooting sprees in Rancho Tehama, California (2017),[33][31][32][34][35] Baltimore, Maryland (2017),[35][34] and Kingsessing, Philadelphia (2023).
[35][34][36] Recently, law enforcement officials in the United States have begun encountering privately made machine gun conversion devices.
[38] On July 8, 2022, former Japanese prime minister Shinzo Abe was assassinated in Nara, Japan, using a homemade "zip-gun" that was electrically fired via a metal filament wire heating up near the propellant.
The GCA also prohibits certain categories of persons, like convicted felons, domestic abusers, current users of illicit drugs and others, from possessing firearms.
[25] While Congress passed the GCA as a response to the assassination of then-President John F. Kennedy, its drafters expressly added that the Act was not intended to place any undue burden on law-abiding citizens who use or make firearms for lawful, private purposes.
[48] On January 4, 2022, Mayor Michael B. Hancock signed into law a bill outlawing certain homemade firearms in Denver, Colorado.
[50][51][52] Since October 1, 2019, all manufactured guns must have a serial number obtained from the Department of Emergency Services and Public Protection engraved.
[53] Any plastic gun that "after removal of grips, stocks and magazines, is not ... detectible" by metal detectors is banned under Connecticut law.
[57] In September 2022, in the case of Rigby v. Jennings, Federal District Court Judge Maryellen Noreika issued a preliminary injunction that barred Delaware from enforcing the portion of the law that restricts the possession and manufacture of untraceable firearms, siding with plaintiffs on their claim that they were likely to succeed on the merits of their Second Amendment claim.
[59] In 2022 Maryland governor Larry Hogan allowed legislation that will, according to The Washington Post, "ban the sale, receipt and transfer of unfinished frames or receivers that are not serialized by the manufacturer" to become law without his signature.
[66][dubious – discuss] In December 2019 Josh Shapiro, then Attorney General, issued a legal opinion that 80% lower receivers are considered firearms.
[67] After a legal challenge, in January 2020 the Commonwealth Court issued a preliminary injunction blocking AG Shapiro's opinion.
[68][69][70] A bill passed by the Pennsylvania House of Representatives in 2024 would make it a third-degree felony to sell or transfer firearm parts without serial numbers.
[71] On July 1, 2020, Representatives Jamie Raskin (MD-08) and David Cicilline (RI-01) introduced House Resolution 7468,[72] aiming to outlaw certain conduct in relation to homemade firearms.
In the Bill's introduction, Rep. Willis stated, "I'm not calling for a ban on them, I'm just saying that you need to have the same background checks as you would if you were going to purchase a regular gun..."[78] On the other hand, the Federal Firearms Licensees of Illinois have voiced 2nd Amendment concerns on behalf of gun sellers: "[Rep. Willis is] trying to make it illegal for the home hobbyist to own or possess firearms they've made.