The serial number puts it around 1966 and it appears to have started life as a fixed sight N frame. It would have been model marked in the yoke cut, but apparently the didn’t mention it.

My guess, it’s a Model 58 that was re-chambered to .45 ACP, re-marked and refinished. It also looks like they shortened the barrel to 3-1/2” and added a target trigger and target hammer.

Whoever did the work did a great job. They were obviously a master. Hamilton Bowen comes to mind.

Edit to add: It also appears that the trigger guard was thinned. Hard to tell from the photos. Awesome combat revolver!

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