The AP5 or Apparatus Pistol, is a roller delayed blowback firearm based and built off of the original and historic design from the 1970s. The roller-lock platform has been widely respected as the preeminent design for over 50 years. Adopted for use across the globe, no other firearm of its type has been more successful. All AP5 firearms are chambered in 9x19 mm and have a cold hammer forged barrel with a 1:9.8 twist.