Running coat
A barrel jacket is a cylindrical body, formerly made of sheet steel, which wraps around the barrel of a rifle (e.g. Gewehr 88 or the Belgian Mauser rifle M 1889) and served as a barrel sleeve in firearms to protect the hand from burns to protect.
Today it is used again in air rifles and air pistols and is mostly made of carbon fiber reinforced plastics . There it is used to ensure that the barrel can swing freely without being influenced.
Demarcation
Cooling jackets are much larger than barrel jackets and are often filled with coolant. The barrel jacket is not to be confused with the handguard that many military weapons have to prevent burns if the barrel is accidentally touched. A gun silencer sometimes resembles the shape of a barrel jacket, but it is also to be distinguished from it.