10mm

The 10mm Auto (10×25mm, official C.I.P. nomenclature: 10 mm Auto, official SAAMI nomenclature: 10mm Automatic) is a semi-automatic pistol cartridge first developed by Jeff Cooper and introduced in 1983 with the Bren Ten pistol. Its design was subsequently improved, then produced initially by ammunition manufacturer FFV Norma AB of Åmotfors, Sweden.