A firearm with varying barrel camming system, the firearm comprising: a longitudinal axis; a frame ; a slide movably supported on the frame for rearward and forward reciprocating movement; a barrel removably coupled to the slide and movable therewith, the barrel comprising a front muzzle end , a rear breech end defining a chamber for holding an ammunition cartridge (C), and axial bore extending between the ends; a camming lug protruding downward from the barrel and including a cam slot defining an upper surface and an opposing lower cam track surface , the cam slot including a rear end and an opposing front end; a cam pin fixedly mounted transversely in the frame , the cam pin arranged to slideably engage the cam track surface when the barrel is carried rearward with the slide under recoil after firing the firearm; the lower cam track surface comprising an initial cam section disposed adjacent the rear end of the cam slot , a concave intermediate varying cam section adjoining and forward of the initial cam section , and a final cam section adjoining and forward of the intermediate varying cam section , the initial and final cam sections each having a different cam profile than the intermediate varying cam section ; wherein the cam pin slideably engages and tracks along the cam track surface after firing the firearm causing the barrel in turn to tilt and uncouple from the slide ; wherein the initial and final cam sections each have a linear cam profile defining a flat surface oriented obliquely to the longitudinal axis of the firearm; wherein the initial cam section of the lower cam track surface is disposed at an angle between and including 15 to 20 degrees to a horizontal reference plane (HP), and the final cam section is disposed at an angle of more than 30 degrees and less than 60 degrees to the horizontal reference plane. a longitudinal axis; a frame ; a slide movably supported on the frame for rearward and forward reciprocating movement; a barrel removably coupled to the slide and movable therewith, the barrel comprising a front muzzle end , a rear breech end defining a chamber for holding an ammunition cartridge (C), and axial bore extending between the ends; a camming lug protruding downward from the barrel and including a cam slot defining an upper surface and an opposing lower cam track surface , the cam slot including a rear end and an opposing front end; a cam pin fixedly mounted transversely in the frame , the cam pin arranged to slideably engage the cam track surface when the barrel is carried rearward with the slide under recoil after firing the firearm; the lower cam track surface comprising an initial cam section disposed adjacent the rear end of the cam slot , a concave intermediate varying cam section adjoining and forward of the initial cam section , and a final cam section adjoining and forward of the intermediate varying cam section , the initial and final cam sections each having a different cam profile than the intermediate varying cam section ; wherein the cam pin slideably engages and tracks along the cam track surface after firing the firearm causing the barrel in turn to tilt and uncouple from the slide ; wherein the initial and final cam sections each have a linear cam profile defining a flat surface oriented obliquely to the longitudinal axis of the firearm; wherein the initial cam section of the lower cam track surface is disposed at an angle between and including 15 to 20 degrees to a horizontal reference plane (HP), and the final cam section is disposed at an angle of more than 30 degrees and less than 60 degrees to the horizontal reference plane. <EOS>