American Rifleman | NATO Standardizes FN’s 5.7×28 mm Cartridge
by Guy J. Sagi –
Thursday March 4th 2021
The 5.7 x 28 mm caliber designed by FN was officially standardized by the North Atlantic Treaty Organization (NATO). Development began in the late 1980s when “Jean-Paul Denis and Marc Neuforge, designers at FN Herstal, started from scratch to design a new cartridge and then a platform for its introduction,” is Dave Campbell’s story for American Rifleman. “The cartridge did not have a superordinate housing. What FN produced was a 1.138 “long case with a rabbet rim and a 35-degree shoulder that fired a 0.22 caliber bullet weighing 23 to 31 grains: 5.7 x 28 mm.” Various commercial firearms are used for this today, including those from FN USA – the FN P90 and the FN Five-SeveN pistol.
The NATO standardization integrates the 5.7 x 28 mm into the organization’s multi-caliber proof and inspection manual (AEP-97) and expands it together with the 9 mm NATO, the 5.56 NATO and the 7.62 into the portfolio of standardized NATO small-caliber ammunition NATO and 12.7 NATO (widely known as .50 BMG).
FN is no novice at accepting and adopting cartridges internationally. She designed the cartridges 5.56 and 7.62 standardized by NATO in 1981 and 1957, respectively. The designation offers armies the guarantee of interchangeability between ammunition from different manufacturers and the operational efficiency of firearms of the same caliber.
NATO was formally established in 1949 and one of its earliest roles was to create ammunition standards that would allow member states to safely procure supplies when needed. There was no such agreement during World War II, when allies came to the front with a potpourri of cartridges of varying dimensions and pressures. As the Cold War got hot, the goal became logistically critical.
With almost three decades of trustworthy use, the FN 5.7 x 28 mm is becoming increasingly popular. “Almost 50 nations are using the 5.7 x 28mm … including the US where no fewer than 19 law enforcement agencies, both federal and state, use it,” explains Campbell. “The cartridge and the cannons intended for it seem to have found approval with special forces and anti-terrorists.”