I recently purchased a used but excelent Walther P22 With a 5" barrell. Took it out to shoot it and was pleased at first. I could shoot stationary 3" clay pigeons @ 50' easily. After about 25 rounds I stopped hitting. Went to a standard 25' pistol target and the best I could do was 3" groups @ 25'. Took it home and cleaned it and tried it again @ 25' paper. At first I was happy again I could keyhole the target, but... after 15-17 rounds the pattern spread again.

I'm wondering if the gun has a barrell issue. Does anyone have any experience with this gun or know anyone who has? I really like this gun 10 minutes at a time.