Embedded Files
Thanks for checking out The Forge Files — Grab a 15% discount on all orders over $100 in the IronKells Shop!
Verdict: Busted!
Claim
Claim
“Loose cartridges in a fire launch bullets like chambered gunfire.” In other words, ammo exploding in a fire will shoot out lethal bullets just as if fired from a gun.
Reality
Reality
No gun, no deadly force. Cartridges outside a firearm lack the chamber and barrel needed to build pressure and propel a bullet at lethal speed.
In a fire, the casing usually fails first – the brass/steel case splits and vents pressure in all directions rather than driving the bullet forward. The bullet may indeed pop out, but at only a tiny fraction of normal muzzle velocity. Tests show these free-flying bullets have extremely low energy – often unable to even penetrate firefighter turnout gear at close range. Injuries from burning ammo are possible up close, but they’re usually from bits of casing or primer (small shrapnel) rather than the bullet itself. In short: it will be loud and chaotic, and standing next to burning ammo is not wise, but it’s nothing like Hollywood scenes of rounds cooking off like machine-gun fire.
Why People Believe It
Why People Believe It
Noise factor: Ammo “popping” in a fire sounds like gunfire. Firefighters and bystanders hear bangs and may assume bullets are flying. In real incidents, 911 callers often report “gunshots” during fires – just the cartridges bursting
This loud noise creates a false impression of high-velocity bullets whizzing around.
Media panic: Sensational news headlines like “House fire ignites thousands of bullets” feed the myth. Such reports emphasize the dramatic sounds and chaos, leading the public to overestimate the danger. The phrase “ammo exploding in blaze” sounds like a massive threat, even though the real hazard is limited.
Misunderstood physics: Many assume a cartridge on its own can propel a bullet as effectively as a gun. People may not realize that without a sturdy chamber to contain the pressure, the powder’s force dissipates harmlessly
The intuitive but incorrect belief is that “a bullet is a bullet,” not accounting for the crucial role of the firearm.
Dramatic visuals: There are plenty of YouTube videos and anecdotes of ammo tossed in fires or ovens, which show shells bursting with sparks and noise. These spectacular visuals can reinforce the myth. It looks like bullets are rocketing off in all directions, even if the actual projectile energy is very low.
Science & Testing
Science & Testing
SAAMI fire-tests: The Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) conducted extensive burn tests (2008 and 2013, with ~400,000+ rounds) to study ammo in fires. Their findings debunked the myth: bullets rarely exceeded on the order of a few hundred feet per second (vs. ~2,000–3,000 fps from a gun)
Lacking confinement, cartridges “burst” and dissipate energy in all directions, preventing any dangerous forward velocity
SAAMI’s key conclusion: “Without chamber support, a cartridge cannot build up enough pressure to propel the bullet at harmful velocity.” The energy instead goes into splitting the case or venting gas
OSHA & SAAMI reports: U.S. safety authorities echo these findings. Firefighter safety bulletins (citing the SAAMI tests) note that the risk is mainly to personnel very close to burning ammo
Beyond a few feet, projectiles lack the speed and mass to penetrate protective gear
In fact, tests showed the most energetic particles were primer cups or casing fragments, not the bullets
Standard firefighter turnout gear can stop those low-mass fragments
The official guidance: keep a safe distance (let it burn out) and focus on fighting the fire – loose ammo is more of a noise hazard than a lethal threat.
MythBusters experiments: MythBusters tested this myth twice (Season 1, Ep.15 “Exploding Ammo” in 2003, revisited 2010). They threw loose rounds into a fire and observed that while the cartridges did burst with loud bangs, the bullets barely had any force – in one test, a bullet from an unchambered round didn’t even penetrate a cardboard dummy a few feet away. Only a cartridge actually loaded in a firearm could launch a bullet with lethal velocity. The team declared the myth “busted”: unchambered ammo simply doesn’t fire with deadly force
A burning pile of loose ammo might sound like a warzone, but it won’t shoot to kill.
U.S. Army & NFPA guidance: Both military manuals and fire codes classify small-arms ammunition as a low-level hazard (Category 1.4S “small explosive”) when it’s in a fire. Their guidelines note that the danger radius is limited – on the order of only a few yards for fragments – and that bullets released by heat lack significant penetration power
The National Fire Protection Association (NFPA) codes treat sporting ammo in a burning building as a minor hazard (no mass explosion risk), advising firefighters to keep back and let the ammunition cook off while controlling the flames from a safe distance. Water can be applied to cool the area; the ammo won’t “blow up” all at once in a chain reaction
In other words, loose cartridges are classified more like fireworks than like bombs when burning – they pop individually and energetically, but not lethally.
Case Law / Real-World Incidents
Case Law / Real-World Incidents
Firefighter injury reports: Despite countless vehicle and structure fires involving ammunition over the decades, there are virtually no documented deaths from loose ammo cooking off. Investigations and industry records show no substantiated cases of firefighters being killed or severely injured by a bullet from exploding ammo
At most, there have been occasional minor injuries (bruises, small cuts or burns), typically when a firefighter was very close and hit by a fragment of casing or a flying primer cap
Even those instances are rare and not life-threatening. One safety bulletin notes that “no fire fighter has been hurt by a flying bullet or shot pellet” in all known fires involving stored sporting ammunition
Ammo cache fires (noise but no carnage): Real incidents underscore the myth’s overestimation. For example, in December 2023 a house fire in Los Angeles ignited thousands of rounds, creating a cacophony of rapid “gunfire-like” sounds
Fire crews initially kept back due to the startling noise, but once the blaze was contained they found no injuries to any firefighters or bystanders
The bullets and shrapnel had not penetrated walls or gear – the ammo mostly just fueled the flames and made a lot of noise. Similarly, fires in firearm warehouses, prop houses, and evidence rooms holding tens of thousands of rounds have resulted in plenty of popped ammo and flying debris, but virtually no serious injuries. Firefighters often describe the scene as “like popcorn popping” but note that beyond a short distance the rounds are harmless. The structures often burn down, but importantly, the exploding ammo doesn’t turn the area into a deadly free-fire zone.
Shop / Train Smarter
Shop / Train Smarter
Ammo storage: Store ammunition in cool, dry places and in stable containers (military-style ammo cans with good seals are ideal). Keep it away from extreme heat sources, open flames, or activities like welding/grinding. While modern ammo is engineered to resist moderate heat, direct fire exposure will eventually ignite it. Good storage won’t prevent a fire, but it can minimize the chance of accidental cook-offs and contain fragments if one occurs.
Fire response: If a building (or vehicle) is on fire and ammunition is present, do not play hero trying to save the ammo. Evacuate and let the professionals handle it. Firefighters are trained and equipped (with helmets, turnout gear, SCBA, etc.) to deal with popping cartridges. Their standard procedure is to keep a safe distance, protect exposures, and douse the flames with water or foam from afar until the ammo has finished burning
You should focus on getting people out and calling 911 – not salvaging your ammo stash. And never reopen a hot ammo can or throw water directly on it; a sudden release of built-up steam/pressure could be dangerous.
Transport discipline: Avoid leaving large quantities of ammunition stashed in a hot car or trunk for long periods. High temperatures alone typically won’t set off cartridges, but prolonged heat can degrade gunpowder and primers over time
This can lead to misfires or erratic performance (or in extreme cases, a primer cooking off). Heat cycling (repeated heating and cooling, as in a car each day) breaks down the chemical stability of the propellant. For both safety and reliability, store ammo at moderate temperatures whenever possible. If you must transport ammo through hot environments, use insulated containers and don’t leave it baking in a closed vehicle all day
Bottom Line
Bottom Line
Loose ammo in a fire is loud and chaotic, but it’s not a battlefield of lethal flying bullets.
A cartridge ignited outside a gun has no barrel to contain the blast – the bullet lacks deadly velocity or range
The danger zone is only a few feet, mostly from small fragments (burst casing or primer) that can cause minor injuries at very close range
Beyond that distance, it’s mostly noise and sparks – scary-sounding, but unlikely to hurt anyone through protective gear or walls.
In any fire, the true threats are still smoke, heat, and structural collapse – not “cook-off” bullets.
Sources / References
Sources / References
SAAMI Technical Data – Sporting Ammunition & the Fire Fighter: Industry burn tests and video demonstrating that unchambered ammunition does not propel bullets with lethal force
OSHA & Firefighter Safety Bulletins (citing SAAMI studies): Official guidance confirming that the main hazard of ammo in fires is localized shrapnel, not flying bullets, and that standard firefighter gear provides protection
MythBusters (2003 & 2010): Empirical tests on Discovery Channel showing loose rounds “cooking off” won’t cause deadly projectile impacts – the myth was busted
NFPA & U.S. Army guidelines (Class 1.4S explosives): Fire codes and military manuals classify small-arms cartridges as a low hazard in fires, with no mass explosion risk and only short-range effects
Firefighter Incident Reports (1980s–present): No recorded fatalities and only minor injuries from loose ammo igniting, per decades of incident data and SAAMI investigations
LAFD Case Study – 2023 Los Angeles Ammo Fire: House fire ignited ~50,000 rounds; lots of “pops” heard, but no injuries to first responders and no projectiles penetrated safety gear or walls
Page updated
Google Sites
Report abuse