When cocked, loaded, and closed; the recoil spring, positioned coaxially around the barrel, provides the pressure necessary to lock the barrel and slide together via the rollers. When a round is discharged, the barrel and slide recoil together while the cam block is held stationary by a lug in the receiver. After traveling rearward a short distance (about 0.16" or 4 mm), the rollers are allowed to disengage from the slide via recesses in the cam block. At this point, the slide is free to continue rearward, cocking the hammer, extracting the spent case from the barrel's chamber, and ejecting it clear of the pistol. After reaching the end of its stroke, the slide is returned to cocked and loaded by the compressed recoil spring, again collecting a fresh cartridge from the magazine and inserting it into the chamber.