a common handgun cartridge among law enforcement agencies and civilians in the United States, while the parent 10mm Auto remains fairly popular. In 2015, SIG Sauer entered the 10mm marketplace with their P220 model chambered in 10mm. Ruger introduced a 10mm auto model to their popular SR1911 line in mid 2017, followed by their Blackhawk, Redhawk and 10mm GP100 Match Champion and Wiley Clapp models in 2018. The Springfield Armory XD-M series added a 10mm offering in late 2018. In November 2021, Smith & Wesson introduced 10mm Auto models in the M&P 2.0 series. In 2022 SIG released the 10mm Auto P320-XTEN in the P320 series. In 2023 Armscor, Colt, Dan Wesson Firearms, Glock, Kimber Manufacturing, Nighthawk Custom, Ruger, SIG Sauer, Smith & Wesson, Springfield Armory, Inc., STI International, and Tanfoglio offer handguns in 10mm Auto. Dimensions The 10mm Auto has 1.56 milliliter (24.1 grain ) cartridge case capacity. 10mm Auto maximum CIP cartridge dimensions The common rifling twist rate for this cartridge is 406.40 mm (1 in 16 inches), 6 grooves, Ø lands = 9.91 mm (.390 in), Ø grooves = 10.17 mm (.4005 in), and land width = 3.05 mm (.120 in). A large or small pistol primer is used. The Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives (C.I.P.; Permanent International Commission for the Proof of Small Arms) rulings indicate a maximum pressure of . In C.I.P. regulated countries, every pistol/cartridge combination is required to be proofed at 130% of this maximum C.I.P. pressure to certify for sale to consumers. The Sporting Arms and Ammunition Manufacturers' Institute (SAAMI) maximum pressure limit for the 10mm Auto is set at . Performance At mid-range potential, the 10mm Auto produces energy higher than an average mainstream .357 Magnum. The 10mm is slightly less powerful than the .357 Magnum with high-performing commercially-available ammunition, or hand-loaded .357 magnums, and well below standard .41 Magnum rounds. The cartridge is considered to be high-velocity, giving it a less arcing flight path upon firing (also termed "flat-shooting") relative to other handgun cartridges. The cartridge case capacity of 1.56 milliliters (24.1 grains H2O) can be a good option for competition, recreational shooting, home defense, and hunting medium to large games. More powerful loadings can basically equal the highest performing .357 Magnum loads, and retain more kinetic energy at 100 yards than the .45 ACP has at the muzzle. The 10mm outperforms the .40 S&W