A firearm includes a frame to which a barrel and slide are slideably mounted and in which a magazine is slideably received. A bumper telescoped on a push rod slideable with the slide pushes a shell in the magazine onto a pivotal carrier. Locking wings pivotally mounted to the barrel are cammed in troughs of a cam block as the barrel and the slide parallel to the longitudinal axis of the barrel relative to the cam block, so that lock tabs are removably received in locking recesses in the slide to removably lock the barrel and slide together. A trigger is slideably mounted to the frame for movement parallel to the longitudinal axis of the barrel for pivoting a sear lever engagable with a biased striker and moving a safety from an interfering position relative to the striker.