Today, I bought a 4" S&W Model 581 357 Magnum. It has the firing pin on the hammer. The serial number is AAC9XXX

There are no signs of it ever having been fired. No blast circles on the cylinder, no brass on the recoil shield, barely a scratch around the cylinder, and a cleaning patch came out WHITE!

This is definitely a service revolver: fixed sights, and it has a non reflective finish along the top of the frame and along the barrel.

How old is my new toy?

TIA

Steve