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I have had this .22 for about 10 years and never touched untill about a year ago. I gave it a once over and noticed it was dirty as hell. Cleaned to shiny and then discovered the trigger problem. Put it away until tonight. Everything seems to function until I install the rear screw in the trigger guard. Once it's all back together I pull the trigger and nothing, then pull it again and it goes boom. What the hell is going on??? I've tried to diagnose the malfunction but to no avail. I've tried everything I can think of but it is consistantly one pull nothing 2nd pull trigger functions. every time same thing. The only thing I can think of is a screw/frame misalignment? Mybe an overtightened rear screw?(I tried to space it with a small washer.) It seems when I first got it I function tested it and it was fine just dirty. Anyone got any ideas? I have no experience with .22 rimfire. I have no ideas left and about to "throw it in the F***ing river" as one of my old friends likes to say. Thanks in advance.