The DPM Mechanical Recoil Reduction System is a direct replacement for the stock recoil rod and does not change the configuration of the gun.
Bull Barrel All Versions
Mechanical Recoil Reduction System Springfield 1911 4″ Compact
This system works due to the multi spring intricate rod (three springs) and controls the functionality of the pistol. The third spring which is contained within the rod controls the movement of the slide so it never rams on the frame.
The external springs are different in length, the long spring is heavy and the short is light so the shooter can fine tune the pistol on the opening and locking positions (slide on the battery) according to his/hers personal standards.