Lever resistance (or load). It is common to call the input force "the effort" and the output force "the load" or "the resistance." This allows the identification of three classes of levers by the relative locations of the fulcrum, the resistance and the effort: These cases are described by the mnemonic "fre 123" where the fulcrum is in the middle for the 1st class lever, the "r"esistance is in the middle for the 2nd class lever, and the effort is in the middle for the 3rd class lever. The lever is a movable bar that pivots on a fulcrum attached to
Lever action are chambered for 12 gauge smokeless shells, while the Winchester Model 9410 shotgun is available in .410 bore. Lever action Lever action is a type of firearm action which uses a lever located around the trigger guard area (often including the trigger guard itself) to load fresh cartridges into the chamber of the barrel when the lever is worked. This contrasts to bolt-action, semi-automatic, or selective-fire weapons. Most lever-action firearms are rifles, but some lever-action shotguns and a few pistols have also been made. One of the most famous lever-action firearms is the Winchester Model 1873 rifle, but many manufacturers—notably