- "What is this, a pirate gun?"
- ―John McClane on the shotgun.
Sawing off a shotgun is a felony under the U.S. National Firearms Act because the weapon is made extremely dangerous, inaccurate and concealable as a result of sawing down the barrels, which gives the gun greater range rather than accuracy. The double-barreled sawn-off shotgun is a favorite among gangs and the mafia, and it was infamously used in the Columbine High School Massacre.
The shotgun seen in the film is a 12 gauge shotgun that was also used in the 2004 Denzel Washington revenge film, Man on Fire. The same armorers for Man on Fire also did A Good Day to Die Hard, so the weapon seen in the film is the same one in Man on Fire. The weapon's appearance in Man on Fire made sense because it took place in Mexico City, however, a Spanish shotgun would really have no place in Russia.
When McClane first sees the weapon, he apparently doesn't realize that it is a sawn-off shotgun, mockingly questioning if it is a flintlock pistol used by pirates. This scene really doesn't make sense, as a New York cop would most certainly have seen multiple sawn-off shotguns in his career, seeing as how they are some of the most commonly used weapons in the world. In fact, Bruce Willis has used them before in his other films, such as 16 Blocks.