105 mm

105 mm (4.1″) is a common and NATO-standard artillery and tank gun calibre.

Since the late 20th century, most NATO armies have centred on 155 mm weapons as having a good compromise between range and destructive power whilst having a single calibre simplifies logistics; however some forces retain 105 mm guns for their portability. The lower power and shorter range of 105mm has led to its obsolescence in full-size self propelled guns such as the American M108 and British Abbot, but the calibre is still popular in towed artillery pieces.

During the Cold War, the concept of the main battle tank was established and guns of 105mm (NATO) and 100mm (Warsaw Pact) were the standard until the advent of 120mm and 125mm guns in the 1960s. The L7 was widely used by NATO countries, and is still used in lighter-weight applications such as the Stingray light tank and the Stryker Mobile Gun System as well as older MBTs.

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