Abstract: A system that allows a person to adjust the tension of the fire control mechanism of a firearm from outside the firearm so the firearm does not need to be disassembled to make such adjustments. The system has a modified mainspring housing or modified grip safety that supports a spring engaging mechanism which engages the sear spring of the fire control mechanism. In one configuration, first and second apertures extend through the housing body and an engaging device, such as a screw, is received in each aperture to contact different segments of the sear spring. From outside the firearm, the user moves a device forward or rearward in an aperture to apply more or less force to the sear spring segment to adjust the fire control mechanism. The sear spring can be modified so a sear spring segment has an enlarged area that is contacted by its engaging device.

Abstract: A system that allows a person to adjust the tension of the fire control mechanism of a firearm from outside the firearm so the firearm does not need to be disassembled to make such adjustments. The system has a modified mainspring housing that supports one or more spring engaging mechanisms which engage the sear spring of the fire control mechanism. In one configuration, first and second apertures extend through the housing body and an engaging device, such as a screw, is received in each aperture to contact different segments of the sear spring. From outside the firearm, the user moves the devices forward or rearward in the apertures to apply more or less force to the subject sear spring segment to adjust the tension of the fire control mechanism. The sear spring is modified so each engaged segment has an enlarged area that is contacted by its engaging device.