Dragon's breath is an exotic incendiary round for a 12 gauge shotgun. Dragon's breath consists primarily of magnesium pellets/shards. When the round is fired, sparks and flames can shoot out to about 100 ft. Dragons breath is normally chambered in 12 gauge 2 3/4" shot shell. The rounds are safe to fire out of an improved cylinder bore as well as a modified choke barrel, common on many shotguns.
While its actual professional combat or tactical usage remains undocumented, the visual effect it produces is impressive and entertaining, similar to that of a short-ranged flamethrower or fireworks, making it popular among gun enthusiasts. Also undocumented, it has been claimed by enthusiasts that the rounds are often used as a distress signal, similar to a very short duration emergency flare gun, though some would argue a flare would be better fitted for such. The round has also been used for intimidation purposes. The pyrotechnic shell is expensive compared to other shells, costing $5 (USD) per round. There is little or no record of its use in actual combat. Because it is a very low-power round, it cannot be used in an auto-loading shotgun or semi-automatic shotgun; it does not produce enough recoil energy to cycle the action, causing the mechanism to fail to cycle. An additional reason to use the round only in a manually operated firearm is that the round shoots at least a little flame for 3–5 seconds. It would be hazardous if a shell still emitting flame were to be ejected from a semi-automatic shotgun.
Illinois law states that a dragon's breath round is any round that "contains exothermic pyrophoric mischmetal as the projectile and is designed for the purpose of throwing or spewing a flame or fireball to simulate a flame-thrower". This shotgun round is banned for use by anyone who is not authorized to possess, manufacture, or sell by the law. The wording is very similar in Florida law as well.
In popular culture
In the FOX show Bones (season 8, ep. 19), Dr. Jack Hodgins suspects a dragon's breath shell could have caused the death of a former Marine sergeant, and the subsequent fire that destroyed the room around him.
FPSRussia shot the Mossberg 500 Chainsaw with dragon's breath ammunition in his YouTube videos, "TOP SHOT :: FN FS-2000 & Mossberg Chainsaw," and "12 Gauge Bullpup!."
In The Dresden Files, the inhuman assassin Kincaid uses dragon's breath rounds to kill Red Court Vampires.
In the TNT show Falling Skies, Jimmy uses dragon's breath rounds to kill two Skitters while on patrol.