JAG1949

I've checked the cylinder lock notches for burrs and deformed metal and I have been unable to perceive any. The cylinder lock itself is shiny on one side but does appear to have worn away any metal. I was advised to check the cylinder lock spring and while it is in place and returns the lock when depressed I have no way to determine whether the spring is correct or has the required tension. I'm in SE Texas between Huntsville and Livingston on the north end of Lake Livingston.

I recently acquired a S&W 625 .45acp revolver. I'm sure it was owned by a competitive shooter because the trigger has a stop installed on the rear surface and there is a ball detent in the top of the crane which securely locks the cylinder in place. The problem is when the trigger is pulled quickly for rapid fire the cylinder often jumps two chambers rather than just one. It cycles normally in slow fire and single action. Upon initial examination I determined the hammer block had been removed. I understand this is a common but by no means safe procedure to speed up the action of the revolver. I replaced the hammer block but it made no difference to the skipping problem when in rapid fire. All this testing has been done with a empty pistol. I'm not about to risk life and limb with a mistimed revolver. Returning it to S&W is an option but I'm comfortable replacing parts on the gun if I know where to start.