' 'Lever action' is the method of cocking the hammer (which bears the firing pin) before the trigger can be pulled in order to release it and strike the cap, thus firing the bullet. A lever action is just that-- a mechanical metal lever that is opened and then closed in order to set the hammer, eject the spent cartridge from the firing chamber and place a new round into the chamber, all at the same time. Neat, eh?
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