Autoloader

In armored warfare, an autoloader or auto-loader is a mechanical aid or replacement for the personnel that load ordnance into crew-served weapons, such as tanks and artillery. The term is generally only applied to larger weapons that would otherwise have a dedicated person or persons loading them.

An autoloader, as its name suggests, extracts a shell and propellant charge from the ammunition storage rack/compartment and loads it into a magazine, if the gun has one, or directly into the chamber of the gun if it does not. It can and often does replace a human loader. By automating the loading process, it can streamline and speed up the loading process, resulting in a more effective fighting machine. In addition, by removing the need for one (or more) crew member, the overall size of the vehicle can be reduced, which in turn reduces the amount of surface area that needs to be armored, and thus a vehicle designed to use an autoloader can benefit from a significant decrease in weight and size. Also, since an autoloader can take up less volume inside a tank than a human, it potentially allows for a lower profile, making the tank harder to hit. Autoloaders are mechanical devices, and therefore their reliability depends on how well they are designed, manufactured, and maintained.

Autoloaders were developed at the beginning of World War II. Their first combat use was in "tank-buster" aircraft such as the 75 mm caliber Bordkanone BK 7,5 cannon-equipped Henschel Hs 129 B-3. Every Soviet- and Russian-derived tank since the T-64 main battle tank has used an autoloader. Their use has been mostly shunned by American and British tanks, although the American T22 medium tank was one of the first to use an autoloader.

In the modern era, autoloading is common on any large (3–inch, or 76.2 mm caliber or greater) naval gun. The size of the shells, when combined with the more elaborate autoloading facilities available in the wider spaces of a ship, makes an autoloader much faster than human loaders. For example, the US 5"/38 Mark 12 can load about 20 rounds per minute.

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