A firing mechanism for a firing pin striker operated semiautomatic handgun that includes a sear, a sear block housing, and a pivot arm. The sear is attached to the pivot arm and includes two angled surfaces and an edge portion for controlling the firing pin. The edge portion abuttingly engages an extension of the firing pin adapted to be in planar movement with the edge portion of the sear. The pivot arm and sear move together in an arcuate path about the pin in response to trigger firing movement. Unlike prior art firing mechanisms, the sear does not move vertically along an axis perpendicular to the bore of the handgun. The arcuate movement of the pivot arm causes the edge portion of the sear to disengage from the firing pin. The angled surfaces of the sear allow the firing pin extension to pass over the sear discharging the firearm.