Arquebusiers

The arquebus (/ˈɑːrkᵻbʌs/ ARK-ə-bus or /ˈɑːrkwᵻbʌs/ AR-kwə-bus) (sometimes spelled harquebus, harkbus or hackbut; Italian Archibugio, Dutch haakbus, meaning "hook gun", or "hook tube") is an early muzzle-loaded firearm that appeared in late 15th century Europe, and was until the 17th century the primary firearm used in European armies. The arquebus was originally a hand cannon with a hook. A matchlock mechanism was added to it around 1475 and it became the first firearm with a trigger. The heavy arquebus, known as the musket, was developed around 1521 to penetrate plate armor. A standardized arquebus, the caliver, was introduced in the early 16th century. The name "caliver" is derived from the English corruption of calibre, which is a reference to the gun's standardized bore. The caliver allowed troops to load bullets faster since they fit their guns more easily, whereas before soldiers often had to modify their bullets into suitable fits, or were even forced to make their own prior to battle. The smoothbore matchlock arquebus is considered the forerunner to the rifle and other long gun firearms.

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Wikipedia