Multiple improvements dramatically increase the reliability and accuracy of a handgun. By combining a plurality of improvements, the accuracy and reliability of a M1911-A1 is dramatically increased. The improvements include a modified sighting system that enables the user to accurately adjust for varying target ranges without losing sight of the targets or altering contact with the weapon. Lubrication notches are incised into the slide/frame interaction regions to prevent fouling. An ambidextrous safety is added that is retained by an interaction with the sear chip shaft. The hammer is modified to provide a region in which foreign matter can migrate to prevent fouling and improve reliability. And the interaction between the sear chip and the hammer is modified to provide a decreased trigger pull that maintains a positive and safe contact between the sear and the hammer at the sear ledge.