P12208523 February 27, 2017 at: 1500 × 1090 In: Modern Personal Defense Weapon Calibers 010: The 9x19mm and 9x21mm Russian Special AP Next → Left to right: 9x19mm ball, 9x21mm 7N28 ball, 9x21mm 7N29 AP, 9x21mm 7BTZ AP-T, 9x21mm SP-12 JHP. Image courtesy of Maxim Popenker