Type Pistol Place of origin United States Production history Designer Smith & Wesson Designed January 17, 1990 Produced 1990 to present Specifications Parent case 10 mm Auto Case type Rimless, straight Bullet diameter 0.4005 in (10.17 mm) Neck diameter 0.423 in (10.7 mm) Shoulder diameter 0.423 in (10.7 mm) Base diameter 0.424 in (10.8 mm) Rim diameter 0.424 in (10.8 mm) Rim thickness 0.055 in (1.4 mm) Case length 0.85 in (21.6 mm) Overall length 1.135 in (28.8 mm) Case capacity 19.3 gr H2O (1.255 cm³) Rifling twist 1 in 16 in (406 mm) Primer type Small pistol Maximum pressure 32,633 psi (225.00 MPa) Ballistic performance Bullet weight/type Velocity Energy 135 gr (8.7 g) Federal Premium JHP Low Recoil 1,190 ft/s (360 m/s) 424 ft·lbf (575 J) 155 gr (10.0 g) Speer Gold Dot JHP 1,175 ft/s (358 m/s) 475 ft·lbf (644 J) 165 gr (10.7 g) Speer Gold Dot JHP 1,150 ft/s (350 m/s) 484 ft·lbf (656 J) 180 gr (12 g) Speer Gold Dot JHP 985 ft/s (300 m/s) 400 ft·lbf (540 J) 200 gr (13 g) Double Tap Hornady XTP JHP 1,050 ft/s (320 m/s) 490 ft·lbf (660 J) Test barrel length: 4 in Source: Midway USA page C.I.P.[1]