I saw this gun at a local gun show today. The cylinder release latch was flat and would open the cylinder by pulling OUT (similar to a Colt revolver) rather than pushing IN like most all other S&W revolvers. Has anyone ever heard of this? Any information would be appreciated. If I recall, the serial number was a six digit number starting with "2."

The Centennial and M40 operate just like any other Smith: push thumb release forward (toward the muzzle).

Something is wrong with the release.

My 1967 flat latch lemon squeezer, model 40 centennial.

Push the cylinder release latch forward, toward the barrel like any other S&W revolver to open the cylinder.
Squeezing the grip safety with the palm of your hand releases the safety and the gun can then be fired.

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