New Mexico does not limit magazine capacity. State law sets no cap on the number of rounds a firearm magazine can hold, and you can legally buy, own, carry, and sell magazines of any size, from a 10-round flush-fit to a 100-round drum. No permit is required for the magazine itself, and no registration exists. The practical cautions sit elsewhere: bills to change this keep appearing in Santa Fe, and several nearby states do restrict capacity.
What State Law Actually Says
New Mexico’s criminal code addresses firearms in Chapter 30, Article 7, covering concealed carry, possession by felons, and negligent use of a deadly weapon. None of those provisions mention magazine capacity, ammunition feeding devices, or any round limit.1Justia. New Mexico Code 30-7-16 – Firearms or Destructive Devices; Receipt, Transportation or Possession by Certain Persons; Penalty There is no legal distinction between a standard magazine and an extended one.
New Mexico does require a background check for all firearm sales, including private transfers, and a licensed dealer can charge up to $35 to process a private-party transaction. Under Section 30-7-7.1, the statute defines a “firearm” as a weapon that expels a projectile by explosion, together with its frame or receiver.2Justia. New Mexico Statutes Section 30-7-7.1 – Unlawful Sale of a Firearm Without a Background Check A magazine on its own does not meet that definition. Buying a magazine, at any capacity, does not trigger a background check under state law.
Concealed Carry Permit Holders
New Mexico’s Concealed Handgun Carry Act restricts what caliber and category of handgun you can carry based on what you qualified with during training, and you can only carry one concealed handgun at a time.3New Mexico Department of Public Safety. Concealed Handgun Carry Act Booklet The act is silent on magazine capacity. If you qualified with a 9mm, you can carry it with a flush-fit 15-round magazine or an extended 33-round magazine without running afoul of the permit rules.
Cities and Counties Cannot Add Their Own Limits
Article II, Section 6 of the New Mexico Constitution reads: “No municipality or county shall regulate, in any way, an incident of the right to keep and bear arms.”4Justia. New Mexico Constitution Article II Section 6 – Right to Bear Arms The language is absolute. It does not permit local governments to be “more restrictive” than the state; it forbids them from regulating at all.
The New Mexico Supreme Court applied that preemption in Baca v. New Mexico Department of Public Safety (2002), holding that the constitutional language was intentionally broad and designed to prevent a patchwork of local rules. Albuquerque, Santa Fe, Las Cruces, and every other local government in New Mexico are blocked from passing their own magazine ordinances. Any capacity limit will have to come from the state legislature.
Bills That Could Change This
The legislature has tried. In 2024, House Bill 137, the “Gas-Operated Semiautomatic Firearms Exclusion Act,” would have defined a “large-capacity ammunition feeding device” as any magazine holding more than ten rounds. The bill died without reaching a vote.5New Mexico Legislature. House Judiciary Committee Substitute for House Bill 137
In 2025, Senate Bill 279 revived substantially the same proposal. It would have banned the import, sale, manufacture, and transfer of magazines holding more than ten rounds, with an exemption for .22 caliber rimfire devices and carve-outs for law enforcement and government agencies. Magazines manufactured before the effective date could still be possessed, but new ones could not be sold or transferred in New Mexico.6New Mexico Legislature. Senate Bill 279 The bill’s final status is not confirmed in the information available here. Check the New Mexico Legislature’s website before you rely on the current rule, because similar bills keep reappearing and the answer in this area could change.
Crossing State Lines
This is where New Mexico’s permissive approach can trip up gun owners who don’t check the laws at their destination. Roughly 15 states and the District of Columbia restrict magazine capacity in some form, with most capping at 10 rounds and a few allowing up to 15 or 20. Colorado, which borders New Mexico, limits magazines to 15 rounds. Driving from Albuquerque to Denver with a 30-round magazine in your range bag can bring criminal charges once you cross the line.
The federal Firearm Owners Protection Act provides a safe-passage provision at 18 U.S.C. § 926A, allowing transport of a firearm through restrictive states if the gun is unloaded and locked in a container outside the passenger compartment, with you traveling between two places where you can legally possess it.7Office of the Law Revision Counsel. 18 USC 926A – Interstate Transportation of Firearms The statute specifically mentions “firearm” and “ammunition” but says nothing about magazines or feeding devices. Whether that protection extends to a high-capacity magazine traveling with the firearm is legally uncertain, and some restrictive states have not treated it as a defense to a magazine possession charge.
Flying out of a New Mexico airport, federal rules require the firearm to be unloaded, declared at the ticket counter, and locked in a hard-sided case in checked baggage. TSA considers a firearm “loaded” if a live round is in the chamber, cylinder, or in a magazine inserted in the firearm.8Transportation Security Administration. Transporting Firearms and Ammunition You must also comply with the laws of your destination. Packing a 30-round magazine in checked luggage satisfies TSA, but if you land in a state that bans it, you face that state’s penalties the moment you pick up your bag.
Federal Law on Magazine Capacity
No federal law currently restricts the number of rounds a magazine can hold. The one time Congress acted was the Public Safety and Recreational Firearms Use Protection Act of 1994, the federal assault weapons ban. That law prohibited the manufacture, sale, and possession of magazines capable of holding more than 10 rounds, with an exemption for those manufactured before September 13, 1994.9U.S. Department of Justice Office of Justice Programs. Impacts of the 1994 Assault Weapons Ban: 1994-96 The law carried a built-in 10-year sunset.10Congress.gov. H.R. 4296 – Public Safety and Recreational Firearms Use Protection Act Congress let it lapse in September 2004, and no replacement has been enacted.
Federal law still regulates who can possess firearms and ammunition. Under 18 U.S.C. § 922(g), prohibited persons — including convicted felons, domestic violence offenders, and people subject to certain restraining orders — cannot possess firearms or ammunition.11Office of the Law Revision Counsel. 18 USC 922 – Unlawful Acts The statute doesn’t name magazines, but a loaded magazine contains ammunition, which adds exposure to an already serious federal offense.
One Thing That Is Not Legal, Regardless of Capacity
Machine gun conversion devices, sometimes marketed as “switches,” “auto sears,” or “chips,” are federally illegal regardless of New Mexico’s permissive stance on magazines. Federal law classifies the device itself as a machine gun, even if it’s never attached to a firearm, and possession carries up to 10 years in federal prison.12Bureau of Alcohol, Tobacco, Firearms and Explosives. U.S. Attorney and ATF Release New Public Service Announcement Warning Against Possession of Machine Gun Conversion Devices These devices are sometimes sold alongside extended magazines online, which creates confusion. Buying a 50-round drum in New Mexico is legal. Buying a switch that makes your pistol empty that drum with one trigger pull is a federal felony.