The FBI’s standard sidearm is the Glock 19M, a compact 9mm pistol built to the bureau’s own specifications. Agents also have access to AR-15 pattern carbines in 5.56mm, pump-action shotguns, and, within specialized units, submachine guns, 1911-platform pistols, and precision rifles. If you were asking what gun the FBI uses day to day on an agent’s hip, the answer is the 19M.
The Glock 19M in Detail
The Glock 19M won the FBI’s sidearm contract in 2016, replacing the .40 S&W Glock 23 that agents had carried since the late 1990s. The contract was worth roughly $85 million and was structured so other federal agencies could piggyback on it. SIG Sauer’s modular P320 was widely expected to win; Glock took the award with a pistol tailored to FBI requirements.
The “M” designation isn’t marketing. The grip has no finger grooves, which lets agents with different hand sizes get a consistent hold. The magazine well is flared for faster reloads under stress. The magazine catch is rounded to bureau specification, and the slide stop is extended and ambidextrous so left-handed shooters can run the gun without breaking their grip. The barrel uses conventional rifling instead of Glock’s standard polygonal rifling, and the trigger uses an FBI-spec connector. It ships with AmeriGlo Agent night sights: a bright orange-outlined front dot with two green tritium lamps at the rear for fast low-light sight acquisition.
Several of these features have since migrated into commercial Glock Gen 5 pistols. A few details remain unique to the M variant.
Off-Duty Carry
Agents working plainclothes or carrying off duty need something smaller than a duty-size 19M. The Glock 26, a 9mm subcompact, fills that role. It conceals easily under light clothing and accepts standard Glock 19 magazines in a pinch, so an agent can carry the smaller gun with full-size magazines as spares.
Rifles and Shotguns
The handgun is the everyday tool. When distance or barriers make a pistol inadequate, agents reach for long guns.
AR-15 pattern carbines chambered in 5.56mm are the primary shoulder-fired weapons for field agents and tactical teams. The FBI selected Aimpoint Duty RDS and CompM4s red-dot optics for these rifles under a five-year contract, with deliveries beginning at the end of 2023. A red dot lets agents acquire targets faster and shoot more accurately under stress than iron sights allow.
Pump-action shotguns, including the Remington 870, round out the standard long-gun options. They serve two purposes: breaching (specialized slugs that defeat door locks and hinges) and close-range defense loaded with buckshot.
Tactical Unit Weapons
The bureau’s elite units carry equipment well beyond what a typical field agent needs.
FBI SWAT teams carry the Heckler & Koch MP5 submachine gun with a collapsible stock, 30-round magazines, a mounted flashlight, and a laser sight. Their sidearm is a Springfield .45-caliber pistol with an 8-round magazine.1FBI. Tools of the Trade – FBI SWAT Text Version
The Hostage Rescue Team has a long relationship with 1911-platform pistols. In the mid-1990s, HRT adopted custom pistols built by Les Baer on the double-stack Para-Ordnance P-14 frame. By 1998, the team transitioned to the Springfield Armory Professional Model, a single-stack 1911 built to HRT’s specifications, with Springfield’s Custom Shop contracted to deliver 500 pistols per year. HRT also fields precision sniper rifles chambered in .308 Winchester and .300 Winchester Magnum for long-range engagements.
The Duty Round
The FBI’s current duty load is the Speer 147-grain G2 Gold Dot jacketed hollow point in 9mm. To qualify as a duty round under bureau standards, a bullet must penetrate between 12 and 18 inches in calibrated 10-percent ballistic gelatin and expand to at least 1.5 times its original diameter. Anything shy of 12 inches may not reliably reach vital structures; anything past 18 inches carries too much risk of exiting the target.2Office of Justice Programs. FBI Bullet Performance Criteria
Rounds are tested through eight different scenarios, including bare gelatin, heavy clothing, sheet steel, drywall, plywood, and automotive windshield glass at both short and longer ranges. The G2 Gold Dot earned its spot by performing consistently across every event. Many competing rounds expand well in bare gelatin but plug up on auto glass or heavy clothing and fail to open.
Why 9mm and Not .40 S&W
The bureau carried .40 S&W pistols from the late 1990s until 2016. Going back to 9mm was not a step down. Modern 9mm defensive ammunition now matches the terminal performance of the .40 S&W loads that were available when the FBI first left the caliber.
Bill Vanderpool, who started the FBI’s Ballistic Research Program, put it plainly: “Technical advances have resulted in very efficient bullets. Forty-S&W pistols are usually 9mms with bigger bores. The nines have proven to hold up better.” The practical case for 9mm stacks up quickly. A Glock 19 holds 15 rounds; the .40-caliber Glock 23 held 13. Recoil is lighter, which means faster follow-up shots and better accuracy, especially for agents who aren’t shooting enthusiasts. And 9mm produces less wear on the frame and slide, so the guns last longer.
Across an agency where every agent must qualify regularly, those advantages compound. Lighter recoil shortens the path to proficiency, lowers ammunition costs, and reduces washouts in qualification.
Can Civilians Buy the Same Guns
Most of what the FBI carries is available to civilians in some form. The details are where it gets interesting.
The Glock 19M has appeared in limited civilian production runs, but the standard Glock 19 Gen 5 shares most of the same features and sits on gun store shelves across the country. The commercial Gen 5 eventually picked up several M-series changes, including the flared magazine well and the removal of finger grooves. For practical purposes, a civilian Glock 19 Gen 5 is very close to what an agent carries.
AR-15 pattern carbines in 5.56mm are legal for civilian purchase in most states, though some states restrict magazine capacity, adjustable stocks, or specific cosmetic features. Aimpoint red dots are available off the shelf.
The harder categories fall under the National Firearms Act. Short-barreled rifles with barrels under 16 inches require registration and a $200 federal tax stamp. Machine guns are the most restricted: the Firearm Owners’ Protection Act of 1986 banned civilian possession of any machine gun manufactured after May 19, 1986, so the select-fire MP5s carried by FBI SWAT teams are off-limits to civilians in that configuration.3ATF. National Firearms Act Semi-automatic MP5 variants that fire only one round per trigger pull are legal but expensive.
The Springfield Armory Professional Model 1911 that HRT carries is commercially available, though the HRT-spec version commands a premium. Springfield’s Custom Shop builds the same gun for civilian sale that it builds for the bureau, which makes it one of the few cases where a civilian can buy the exact firearm an elite federal unit carries.