I had the exact same problem with my 625 PC. I took off the grips and found the strain screw had backed out. I put some red loctite on the threads and tightened all the way down..haven't had a problem since, as a matter of fact just fired off 200 today. Some guys here change out the firing pin to a extended one. I never had to go that far. The majority of my shooting with the 625 is now done with Auto Rim brass but I like to use the moon clips on occasion since I have quite a few ACP loaded up for my 645 SW auto. Hope this helps !

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