5.7×28 FN

The 5.7x28mm SS190 round was developed by the FN Herstal Company of Belgium.  FN started the development of this new ammunition in 1986. Originally this caliber was intended for a sub machine gun type personal defence weapon developed under the codename “Project 9.0”.

The new cartridge represented a typical scaled-down rifle cartridge, with a relatively long, bottlenecked rimless case and a long, pointed bullet. Early bullets, known as the 5.7mm SS90, had metal jackets and lightweight plastic cores. However, with the intention of improving penetration against body armor, in 1994 FN developed a heavier SS190 AP bullet with a composite core. This bullet consisted of hardened steel at the tip and aluminum in the body.

Later on, several other types of bullets were introduced, including the heavier SB193 for subsonic loads, the tracer L191 and the ‘practice’ SS192 with a soft core instead of a steel penetrator. So far the only mass-produced service handgun that fires this ammunition is the Belgian-made FN Five-seveN pistol. It is also used in it’s ‘sister gun’, the FN P90 sub-machine gun. Also a few commercial semi-automatic carbines made in the USA for the civilian market.

*) when fired from FN Five-seveN pistol