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New NATO Caliber – FN Herstal's 5.7x28mm
Thirty-five years after it was invented, the 5.7x28mm caliber is now standardized by NATO. The new standardization comes after the 5.56x45mm and 7.62x51mm calibers, which were both designed by FN Herstal, and standardized by NATO in 1957 and 1981 respectively. Two other NATO calibers are the 9x19mm NATO and the 12.7x99mm NATO. The main use for the 5.7x28mm is for handguns and Personal Defense Weapons (PDW) like the FN P90.
