I have an M&P 340 which recently when opening the cylinder on my 340 the cylinder slid past he frame stop. It appears that the frame stop is pretty skimpy in comarison to my 617 and 629. It seems there may be only a few thousands of overlap between the edge of the cylinder and the stop on the frame. Nothing seems bent and no undue force was used in opening the gun. Any thoughts? Thank you.

I had the same issue a while back. The stop is not very big, and with a slight bend in the crane, the cylinder can come completely off of the gun.

You will have to send it back to S&W and they will likely replace the frame.....that is what they did in my case anyhow....they put my barrel ect on a new frame.

The S&W warranty is good and if you get a decent rep on the phone, things will happen quickly. You might try and angle for some extra service while they are paying for the shipping...maybe an action package?

Good luck.

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