A bolt-action
firearm is typically a
rifle in which the opening and closing of the
breech is controlled manually by a bolt. Typically, the
bolt consists of a tube of metal inside of which the firing mechanism is housed, and which has at the front or rear of the tube several metal knobs, or "lugs", which serve to lock the bolt in place. The operation can be done via a
rotating bolt, a lever, or a number of systems. For example, one setup is a straight-pull design that use a rotating bolt, such as the German
Blaser R93 rifle. Straight-pull designs have seen a great deal of use, though manual turn-bolt designs are what is most commonly thought of in reference to a bolt-action design due to the type ubiquity. As a result the bolt-action term is often reserved for more modern types of rotating bolt-designs when talking about a specific weapon's type of action, however both straight-pull and rotating bolt rifles are types of bolt-action rifles.
Lever-action and
pump-action weapons must still operate the bolt, but they are usually grouped separately from bolt-actions that are operated by a handle directly attached to a rotating bolt.
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