Intermediate cartridge

An intermediate cartridge is a rifle/carbine cartridge that is less powerful than typical full-power battle rifle cartridges, such as the .303 British, 7.62×54mmR, 7.92×57mm Mauser or .30-06 Springfield, but still has significantly longer effective range than pistol cartridges. As their recoil is significantly reduced compared to high power rifle cartridges, fully automatic rifles firing intermediate cartridges are relatively easy to control. However, even though less powerful than a traditional rifle cartridge, the ballistics are still sufficient for an effective range of 250–500 metres (270–550 yd), which are the maximum typical engagement ranges in modern combat. This allowed for the development of the assault rifle, a selective fire weapon that is more compact and lighter than rifles that fire full power cartridges. The first intermediate cartridge to see widespread service was the German 7.92×33mm Kurz used in the StG 44. Other notable examples include the Soviet 7.62×39mm used in the AK-47 and AKM series, and the American 5.56×45mm NATO cartridge first used in the M16.

The Second World War saw the use of the bolt-action rifles such as the Mauser Karabiner 98k, the Lee–Enfield SMLE, the Mosin–Nagant, the Arisaka Type 38, and Type 99 rifles, and during the early years, the Springfield M1903, as well as semi-automatic battle rifles such as the Gewehr 43, the M1 Garand, and the SVT-40. These rifles weighed over 8 lb (3.6 kg), and they were longer than 40 in (1,000 mm) and as such inappropriate for close combat. They fired cartridges capable of killing out to 1,000 m (1,100 yd). In close quarter combat, all the major armies began employing submachine guns such as the PPSh-41, Thompson M1928A1, and the MP-40, all of which fired pistol cartridges. Compared with the battle rifles, these submachine guns could provide high rates of controllable fire, but they lacked the power and longer effective range of the battle rifles.

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