I recently received a model 39-2 and there appears to be an issue with the trigger. The trigger does not seem to be operating properly. The hammer cocks as it should but the trigger will not release the hammer. You can squeeze the trigger and it moves freely but does nothing. The trigger will not move the hammer in double action OR single action. What puzzles me is, when you take the slide and barrel off of the frame everything works perfectly. The trigger works in double action and single action. Something is not catching like it should once the slide is on the frame.
Does anyone have any ideas on what part might be the culprit?

If you are new to the 39 and it's relatives, do you have the magazine inserted when you are testing for function? The magazine safety does not allow the trigger/hammer group to work without the magazine being fully inserted.
Make sure your magazine and chamber is (are) empty of ammunition when you start testing for function. I know it sounds like a no brainer but negligent discharges do happen when your trying to work out a problem and concentrating.

Sounds like the drawbar is not in it's proper position when the gun is fully assembled. (being held down by something) Check the mag disconnect/ejector lever, disconnector, etc. Make sure the levers have been assembled properly. Might try fully disassembling/cleaning/reassembling the lower frame and parts to see if that helps.

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Ret. LE, FA Instr, S&W Armorer

IAM NEW TO THIS SITE AND HAVE A QUESTION. I OWN A S&W 39-2 AND BOUGHT A NEW CLIP LAST WEEKEND AT A GUN SHOW. THE CLIP IS THE SAME AS MY OTHERS,HOWEVER IT WONT CATCH WHEN I PUT IT IN I'VE GOTTEN DIFFENT INFO FROM OTHER DEALERS,SOME SAY MY 39-2 WAS BUILT TO HOLD 9 ROUNDS IN THE CLIP,BUT 3 OF THE OTHER CLIPS I HAVE ONLY HOLD 8. THE NEW CLIP WILL ONLY HOLD 8 BUT WILL NOT LOCK IN PLACE WHEN I PUT IT IN. WHAT IS THE DIFFERENCE IN THESE TWO PISTOLS..

Yes, the 39-2, like most of the S&W autos, the Browning High Power and others, has a magazine safety. The trigger will not function unless a magazine is in the pistol. You can dry fire, just make sure you have an EMPTY magazine in the pistol.

Another way of dealing with the issue is to take one magazine, mark it clearly as deactivated, remove the spring and follower and use that for dry firing to make sure you do not accidentally chamber a round. Without the follower, the slide will not lock back, but the body of the magazine still overrides the magazine safety.

The 39-2 took a magazine that held 8 rounds. The later 39 Series guns, such as the 3904, which is a 3rd Gen gun, will not work with the original 39-2 magazine as it is too short to engage the mag catch.

If you have an real factory mag for a 39-2, it should work.