As SmithNut wrote, there are several threads about the 3914DAO. For years it was a mystery of sorts. Even the SCSW had little knowledge about the existence of this model.

They were made in both Springfield, MA and Houlton, ME. Mine is a Houlton made gun which I purchased from a NYPD officer who moved to a different department that specified a different firearm for off duty carry.

The "true" DAO guns are built differently than the 3914. The 3914 was created by producing a hammer that had no single action notch and removing the safety lever.

I converted a S&W 457 to DAO by filing down the single action notch on a hammer I bought on Ebay. I converted it back because firing 50 rounds on that gun tortured my forearm.

BTW, there is a 457D. Two versions as it happens. One was made by doing the same thing that Smith did to make the 3914DAO. The other is a true DAO. Both were made exclusively for Chicago PD. I think it was the second version that made it into production.

Those guns are more scarce than the 3914DAO. I've seen exactly one for sale and that was on this forum a few years ago.

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