A trigger mechanism has a hammer, a hammer spring, a trigger pull, a trigger spring, a pivotal linkage between the trigger pull and a sear which has a cam surface and a guide. The hammer has striking and bearing ends and a pivot point between the ends. The hammers' bearing end rides up on the cam surface as it moves between different positions relative to the guide. The hammer pivots around the pivot point and the striking end is moved between the hammer's seated and cocked positions as the cam surface moves between its positions. The hammer spring has opposite ends connected to the firearm's frame and the hammer, respectively, which provides a hammer spring force. The hammer spring biases the striking end of the hammer to the seated, striking position and the movement of the hammer to its rearward position is performed against the hammer spring force.