Just a note on the 645 (I have one). The screw that goes through the right-hand safety has a tendency to work loose. A drop of blue Lok-Tite should fix that. The single action trigger pull is complex and would probably be hard to tune. I don't like the take-up and over-travel before and after the letoff. If you have a fleshy trigger finger, you can get a bit of flesh caught behind the trigger after letoff.

On the plus side, the gun is completely reliable and will even feed empty cases from the magazine. All I did to mine was polish the feed ramp, and that was probably unnecessary. I bought mine new many years ago, and got a Galco pancake holster for it. I don't know if they are still making them.

Hope this helps.

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