Firearms banned in California include assault weapons, machine guns, short-barreled rifles and shotguns, .50 BMG rifles, destructive devices, unserialized “ghost guns,” and a long list of concealed or disguised weapons such as cane guns and wallet guns. The state also prohibits or tightly restricts silencers, large-capacity magazines, bump-fire stocks, and certain kinds of ammunition. Penalties range from a $100 infraction fine for possessing an older large-capacity magazine to eight years in state prison for manufacturing or selling an assault weapon.
Assault Weapons and .50 BMG Rifles
California defines “assault weapon” mostly by feature rather than by brand, though certain models are banned by name under Penal Code 30510. The feature-based rules in Penal Code 30515 are where most owners get caught out, because a single attachment can push an otherwise legal firearm into banned territory.
Rifles
A semiautomatic centerfire rifle counts as an assault weapon if it has a detachable magazine plus any one of the following: a pistol grip that protrudes conspicuously beneath the action, a thumbhole stock, a folding or telescoping stock, a grenade or flare launcher, a flash suppressor, or a forward pistol grip. A fixed-magazine centerfire rifle qualifies if it holds more than 10 rounds, and any centerfire semiautomatic rifle with an overall length under 30 inches also qualifies.1State of California Department of Justice – Office of the Attorney General. Assault Weapons Laws (California and Federal Law)
Pistols and Shotguns
A semiautomatic pistol is an assault weapon if it lacks a fixed magazine and has a threaded barrel, a second handgrip, a barrel shroud that lets you fire without burning your hand, or the ability to accept a magazine outside the pistol grip. A semiautomatic pistol with a fixed magazine holding more than 10 rounds also qualifies. For shotguns, the triggers are a folding or telescoping stock combined with a pistol grip or thumbhole stock, a detachable magazine, or a revolving cylinder.1State of California Department of Justice – Office of the Attorney General. Assault Weapons Laws (California and Federal Law)
.50 BMG Rifles
Any rifle chambered in .50 BMG is classified as an assault weapon under Penal Code 30510 and carries the same prohibitions and penalties.
The Featureless Configuration
Owners can build or modify a rifle to remove every feature that triggers the classification. A featureless AR-platform rifle might use a fin grip in place of a standard pistol grip and a fixed stock instead of a collapsible one. With none of the prohibited features and a fixed magazine of 10 rounds or fewer, the rifle does not meet the legal definition of an assault weapon. This is the most common way Californians legally own semiautomatic centerfire rifles.
Penalties
Manufacturing, distributing, transporting, importing, selling, or lending an assault weapon or .50 BMG rifle is a felony carrying four, six, or eight years in state prison. Transferring one to a minor adds a consecutive one-year enhancement.2California Legislative Information. California Penal Code 30600 Possession of an unregistered assault weapon is a separate offense that California prosecutes as either a misdemeanor or a felony depending on the circumstances.1State of California Department of Justice – Office of the Attorney General. Assault Weapons Laws (California and Federal Law)
Machine Guns
Possessing or knowingly transporting a machine gun is a felony punishable by state prison time, a fine of up to $10,000, or both. Intentionally converting a standard firearm into a machine gun carries a harsher sentence of four, six, or eight years in prison.3California Legislative Information. California Penal Code 32625
Short-Barreled Rifles and Shotguns
A short-barreled rifle has a barrel under 16 inches or an overall length under 26 inches. A short-barreled shotgun has a barrel under 18 inches or an overall length under 26 inches. Manufacturing, importing, selling, lending, or possessing either type is punishable by up to one year in county jail or by a state prison sentence.4California Legislative Information. California Penal Code 33215
Destructive Devices
Penal Code 16460 defines “destructive device” broadly. Some of what it covers is military hardware most people will never see, but a few categories catch civilians off guard:
- Explosive or incendiary projectiles, including tracer and incendiary ammunition. Shotgun tracer rounds manufactured specifically for that purpose are the only exception.
- Bombs, grenades, explosive missiles, and launchers designed to fire them.
- Any firearm with a bore greater than .60 caliber that fires fixed ammunition, unless it is a standard shotgun, an antique rifle, or an antique cannon.
- Rockets or rocket-propelled projectiles over .60 inches in diameter, and any rocket containing explosive or incendiary material beyond its own propellant. Emergency signaling devices are excluded.
- Sealed containers designed to explode through chemical reaction, such as dry-ice bombs.
Making, possessing, or transferring these items carries felony consequences.5California Legislative Information. California Penal Code 16460
Disguised and Improvised Firearms
Penal Code 16590 lists items California classifies as “generally prohibited weapons.” Most are knives and martial-arts weapons, but several are firearms:
- Cane guns, which are firearms concealed inside a walking cane.
- Wallet guns, designed to be carried in a container resembling a wallet.
- Undetectable firearms that cannot be picked up by metal detectors or standard airport X-ray machines.
- Flechette dart ammunition, containing small dart-like projectiles.
- Zip guns, meaning improvised firearms not made by a licensed manufacturer.
Each item is tied to a specific code section that sets out the prohibition and penalty. Violations generally carry up to one year in county jail or a state prison term.6California Legislative Information. California Penal Code 16590
Ghost Guns and Unserialized Firearms
If you manufacture or assemble any firearm in California, you must first apply to the California Department of Justice through the CFARS system for a unique serial number. That number must be permanently engraved or embedded on the firearm before you possess or transfer it.7Cornell Law School. Cal. Code Regs. Tit. 11, 5515 – One Unique Serial Number Issued Per Firearm or Firearm Precursor Part
Possessing, selling, or transferring an unserialized firearm or its precursor parts without complying with these requirements can bring misdemeanor or felony charges. The rule applies to completed firearms and to unfinished frames or receivers that can be readily converted into functioning weapons.
The Unsafe Handgun Roster
California keeps a roster of handguns certified as meeting the state’s safety requirements. Licensed dealers cannot sell any new handgun that is not on the list. Penal Code 31910 defines an “unsafe handgun” as any concealable pistol or revolver that fails to satisfy specific criteria, including a chamber load indicator, a magazine disconnect mechanism, and microstamping capability. Because virtually no new models have been added in recent years, many popular handguns available in other states cannot be bought from a California dealer.
Off-roster handguns are not illegal to own. You can still acquire one through a private party transfer, inheritance, or certain law enforcement exemptions.
Prohibited Accessories
Large-Capacity Magazines
A large-capacity magazine is any ammunition feeding device that holds more than 10 rounds. Manufacturing, importing, selling, lending, buying, or receiving one is punishable by up to one year in county jail or a state prison sentence. Possession, regardless of when the magazine was acquired, is an infraction punishable by a fine of up to $100 for a first offense, though later violations can be charged more seriously.8California Legislative Information. California Penal Code 32310
The ban has been in litigation for years. In March 2025, the Ninth Circuit sitting en banc ruled in Duncan v. Bonta that California’s magazine ban is consistent with the Second Amendment, reversing a lower court that had struck it down. The en banc court found that large-capacity magazines are not protected “arms” under the Second Amendment’s text and that, even if they were, the ban fits within the nation’s historical tradition of regulating especially dangerous weapon components.9Justia. Virginia Duncan, et al v. Rob Bonta, No. 23-55805 (9th Cir. 2025) The ban is currently enforceable.
Silencers
Possessing a silencer, also called a suppressor, is a felony punishable by state prison time, a fine of up to $10,000, or both. Unlike many states where suppressors are legal with a federal tax stamp, California provides no civilian pathway to legal ownership.10California Legislative Information. California Penal Code 33410
Bump Stocks and Trigger Cranks
Devices that increase a semiautomatic firearm’s rate of fire fall under California’s ban on “multiburst trigger activators.” Making, importing, selling, lending, or possessing one is punishable by up to one year in county jail or a state prison sentence.11California Legislative Information. California Penal Code 32900 California banned these devices well before the federal bump stock rule, which the Supreme Court struck down in 2024. The state ban remains fully in effect regardless.
Ammunition Restrictions
Armor-Piercing Handgun Ammunition
California bans possession of handgun ammunition designed primarily to penetrate metal or armor. A conviction carries up to one year in county jail or a state prison term, plus a fine of up to $5,000. One detail matters: this statute covers ammunition for handguns. Steel-core rifle ammunition is not prohibited under it.12California Legislative Information. California Penal Code 30315
Separately, tracer and incendiary ammunition for any firearm is treated as a destructive device under Penal Code 16460, with an exception only for tracer rounds manufactured specifically for shotguns.5California Legislative Information. California Penal Code 16460
Background Checks on Every Ammunition Sale
Since July 2019, California has required a background check for every ammunition purchase. If your information matches an existing record in the state’s Automated Firearm System, the check costs $1 and processes quickly. If it does not match, you need the more thorough check, which costs $19 and takes longer.13State of California Department of Justice. Text of Adopted Regulations – Ammunition Eligibility Checks If the system determines you are a prohibited person, the sale is denied. You cannot buy ammunition anonymously in California, even at a gun show.
Who Cannot Possess Any Firearm
Beyond the weapon-specific bans, certain people are barred from possessing any firearm at all. Under the federal Gun Control Act, you cannot ship, receive, or possess a firearm if you have been convicted of a felony, are a fugitive, use controlled substances unlawfully, have been committed to a mental institution, are subject to a domestic violence restraining order, or have been convicted of a misdemeanor crime of domestic violence, among other categories.14ATF. Identify Prohibited Persons
California adds its own categories on top of the federal list, including people convicted of certain misdemeanors, those with outstanding felony warrants, and individuals subject to gun violence restraining orders. For anyone in a prohibited category, possession of even a standard handgun or hunting rifle is a criminal offense.